Yuuto Kiba is one of the male protagonists of High School DxD. He is a third-year high school student at Kuoh Academy in Class 3B and the school's pretty boy who is adored by many female students and hated by other male students. He is Rias' Knight and a member of the Occult Research Club.
Yuuto is a handsome young man with short blond hair, blue eyes (bluish gray eyes in the anime) and a mole underneath his left eye.
He wears the Kuoh Academy boys' school uniform, which consists of a black blazer with white accents over a white, long-sleeved dress shirt with a black ribbon on the collar, matching black pants, and brown dress shoes.
Yuuto is overall an upbeat person and cares deeply for his comrades. He's also a very polite and friendly individual, even considering Issei's initial dislike towards him. As a Knight, he has pride, chivalry, dignity, and honor befitting one, and is shown to enjoy fighting fellow swordsmen like Karlamine.
Initially, he had a deep hatred towards the Holy Swords or its wielders. But the efforts of the Occult Research Club members during Volume 3, and the souls of his deceased friends, who died earlier being victims of the Holy Sword Project, helped him overcome his drive for vengeance, making him more acceptable of the Holy Swords.
Yuuto considers Issei to be his best friend, but also feels a sense of rivalry with him, wishing to one day fight him fair and square. At the same time, he also shows deep concern for his well-being, desiring to avenge Issei after his death in Volume 11 and only stopping himself due to promising to protect the girls of the Club in his stead.
Yuuto is very loyal to Rias as her Knight, calling himself Rias Gremory's Sword while also thinking of her as his own older sister. He did not hesitate in joining Rias' team for the Azazel Cup even with the possibility of eventually facing Issei, taking it as a chance to settle their rivalry and swearing to not hold back against him.
Yuuto is surprisingly a lecher himself, as commented by Issei in Volume 4.
Originally an orphan named Isaiah, Yuuto was taken in by the Church and was chosen to be a part of a project called "The Holy Sword Project" under the supervision of Valper Galilei. But when the Project failed to show merit, Valper's decision to eliminate them as failures, was directly responsible for the deaths of his friends and all other participants, resulting in Yuuto developing extreme antagonism against Holy Swords especially Excalibur. After successfully escaping the facility with the help of his friends, he finally succumbed to the poison he inhaled. Lying on the ground, he was in his dying moments when he was found and was reincarnated by Rias as her servant Devil. During his initial days as Rias' servant, he was distrustful of her and all those related to her. He later practices his swordsmanship under Souji Okita, who was the first person he opened up to. One day, when giving tribute to his deceased friends, he was confronted by a stray Devil and fought a hard battle until his master, Okita, comes to rescue him. After this event, he finally began trusting Devils, opened up to Rias and took upon the name Rias thought of specifically for him, "Yuuto Kiba".
Yuuto made his appearance in Volume 1, bringing Issei Hyoudou to the Occult Research Club under Rias' orders. He later assisted Issei in his attempt to save Asia Argento from the Fallen Angel Raynare.
In Volume 2, after the announcement of the Rating Game match between his master and her fiancé, Riser Phenex, Yuuto accompanied his allies to a training camp in the mountain for a week. He later participated in the Rating Game where he successfully defeated Riser's three Pawns: Shuriya, Marion, and Bürent before being eliminated by Riser's Queen, Yubelluna. He was then seen attending Rias' engagement party where he helped Issei fend off the security to open up a path for his new friend.
In Volume 3, Yuuto's past came back to haunt him again after seeing Issei's photo as a child with Irina Shidou and her father who is holding a Holy Sword. This only got worse after the appearance of Irina and Xenovia Quarta who were ordered to retrieve the stolen Excalibur swords. Issei eventually manages to make a temporary alliance with the Church duo, where they will help the two of them retrieve the Excaliburs in return for giving Yuuto a chance to let go of his past and move on by destroying the Holy Sword once and for all. This also allowed Yuuto to learn of the person in charge of the Holy Sword Project, Valper Galilei. The team was eventually attacked by Freed Sellzen and Valper which causes Yuuto to chase after them. Yuuto later returns to help his friends in their fight against the Fallen Angel Leader Kokabiel, Freed, and Valper. He eventually learns the truth behind the Holy Sword Project, and with the help of his friends' spirits from the light-attribute crystal, Yuuto was able to achieve his Balance Breaker, the Sword of Betrayer. He, then, goes on to break the stolen Excalibur with the help of Xenovia. The Occult Research Club was then confronted by Kokabiel and was overwhelmed by the latter until the intervention of Vali Lucifer who came to retrieve Kokabiel under Azazel's orders.
In Volume 4, during the meeting between the leaders of the Three Factions which was interrupted by the sudden attack from the Khaos Brigade's Old Satan Faction leader, Katerea Leviathan, Yuuto assisted in fighting off the magicians from the Khaos Brigade along with Xenovia. Yuuto also gave a Holy Demonic Sword to the Archangel Michael in exchange for not allowing any Holy Sword research facility to produce more victims.
In Volume 5, Yuuto, like the rest of Rias' peerage, returned to the Underworld for the Young Devils Gathering. In the Underworld, Yuuto trained in maintaining and using his Balance Breaker for long fights. During the Rating Game between his master and Sona Sitri, he and Xenovia faced off against Tsubaki Shinra, Tomoe Meguri, and Tsubasa Yura. Yuuto was able to defeat Tomoe and Tsubasa by using the new technique formed by him and Xenovia, "Durandal Birth", which combines the holy aura of Durandal and the holy-demonic swords that sprung forth from the ground. Near the end of the match, he chased after Tsubaki but was temporarily interrupted by Akeno before going on to eventually defeat Tsubaki.
In Volume 6, during Rias and Diodora Astaroth's Rating Game that was interrupted by the Khaos Brigade, Yuuto fought Freed Sellzen, who had turned into a Chimera, easily cutting his body to pieces before destroying his head, killing the latter. He later shielded the members of the Gremory group with multiple holy-demonic swords from the impact of the Longinus Smasher. He, along with the rest of the Gremory Team, was last seen cheering for Issei and Asia on their three-legged race.
In Volume 7, after fending off the Sacred Gear users and anti-monsters sent by the Hero Faction of Khaos Brigade, Yuuto tagged along with Rias, Asia, and Gasper to spy on Issei and Akeno's date, but soon lost them when Issei and Akeno escaped. The Occult Research Club was then asked to serve as Odin's bodyguard as they are attacked by the Norse Evil God Loki and Loki's son, Fenrir. The Occult Research Club, along with Baraqiel, Rossweisse, and Saji, later teamed up with the Vali Team to fight their final battle against Loki and Fenrir.
In Volume 9, during his trip to Kyoto with the second year students of the Occult Research Club, the team crossed path with Khaos Brigade's Hero Faction after the latter kidnapped the leader of the Youkais, Yasaka. In the battle to rescue Yasaka, Yuuto and Xenovia fought against Siegfried but were easily defeated by him.
In Volume 10, after being defeated by Siegfried, Yuuto trained to achieved the Balance Breaker of Blade Blacksmith which he reveals in his fight against Beruka Furcas during Rias and Sairaorg Bael's Rating Game. Yuuto, Rossweisse, and Xenovia then faces Sairaorg in a three-on-one battle but lost to the latter (although they managed to cut off one of Sairaorg's arms).
In Volume 11, Yuuto received a promotion recommendation along with Akeno and Issei. While the group was resting after the test, they were ambushed by Cao Cao and Georg who came to steal Ophis' powers. The battle ended with the Gremory and Vali Teams losing to Cao Cao and Ophis' powers getting stolen. Both teams were then attacked by a legion of Grim Reapers and Siegfried. He, then, has his rematch with Siegfried, which ended with Yuuto cutting off one of Siegfried's Dragon Arms. Like the other members of the Gremory Team, Yuuto was shocked to learn that Issei had "died" at the end of Volume 11.
At the beginning of Volume 12, Yuuto and the other members of the Gremory Team stayed in the Gremory Palace, while the whole team was still in shock with Issei's death, especially Rias and Akeno. Yuuto later goes to the basement of the Gremory Palace to check on the Vali Team while asking the original Sun Wukong about Samael's curse. The Gremory Team later goes to the Human world to ask the creator of the Evil Pieces, Ajuka Beelzebub, to check on Issei's Evil Pieces and was surprised to see the Old Satan Faction and Siegfried who had come to offer an alliance with Ajuka. He, then, faces off once more against Siegfried in their third and final encounter. During the fight, Siegfried uses Chaos Break which makes his body undergo a demonification process to transform into a monstrous spider all while fusing with his Demon Swords and Sacred Gear. With this new form, Siegfried easily overwhelms all the members of the Gremory Team, cutting off Yuuto's left arm (which he was able to reconnect later in the battle through the combined efforts of Ravel, Koneko, and Asia) and injuring both of his legs. The battle was overturned when one of Issei's Evil Pieces transformed into the sword Ascalon, allowing Yuuto to injure Siegfried. Siegfried finally lost to the latter after his strongest Demon Sword, Gram, left him and chose Yuuto as its new wielder. As he received attacks from the Gremory Team with Yuuto dealing the final blow by stabbing him with both Gram and Ascalon, his body started to crumble away. After the battle, Siegfried's remaining Demon Swords chose Yuuto as their new wielder. After Cao Cao's defeat, Arthur challenged Yuuto after deeming him to be a worthy opponent for his Holy King Sword, telling Yuuto that he will fight him when Vali fights Issei, which he quietly accepts. At the end of the same volume, Yuuto is also officially promoted into a Middle-Class Devil.
In Volume 14, Yuuto is shown to be training Xenovia on how to better use her Ex-Durandal, claiming that should Xenovia master all seven abilities of the Excalibur in addition to the Durandal, she would surpass him as a swordsman. He later goes to Romania along with Rias and Azazel in order to find out more about Gasper's unknown power.
In Volume 15, Yuuto accompanies Rias who was staying at the House of Vladi until a Vampire from the House of Tepes asked them to meet the current leader of the Tepes Faction, Valerie Tepes, much to the surprise of the two.
In Volume 16, Yuuto and Rias reunited with their friends who came to the Tepes territory. He later participated in rescuing Valerie from Marius Tepes who attempted to extract the Longinus, Sephiroth Graal, from Valerie where he and his friends fought against the modified Vampires and Grendel. After Rizevim turns all of the modified Vampires into mass-produced Evil Dragons, Yuuto and Rossweisse teamed up together to fend off the mass-produced Evil Dragons. After returning to Japan, Yuuto participated in the meeting for the formation of D×D.
Yuuto, along with the other members of the Occult Research Club, went to the Underworld in Volume 17 and participated in the experience day for the school Sona Sitri built located at Auros in the Agares territory. While doing the respective activities assigned to them, Qlippoth managed to surround both Auros and Agreas inside a barrier and announced their intent to attack after a certain period of time. Before the time was up, they reconfirmed their plan and Yuuto ended up pairing with Tsubaki of the Sitri group and fought against the mass-produced Evil Dragons.
Yuuto and the Occult Research Club went to Heaven in Volume 18 to talk to Michael about the Christmas project the alliance is working on. After the meeting, Michael informed them about the death of Church officials and the presence of Evil Dragons were present. Yuuto helped defend Heaven from the attack of Qlippoth. He, along with Rias, Koneko, Gasper, Akeno, Rossweisse, and Cao Cao, fought against the Evil Dragon Ladon and three of Grendel's clones. He was able to successfully defeat a clone with the help of Rossweisse and Akeno. After all the fights were settled, Yuuto and the Occult Research Club celebrated Christmas and it was announced that he will succeed Akeno as the new Vice-President of the club.
In Volume 19, Yuuto participated in the fight against the exorcists that rebelled against the Church. He requested to transfer to the group that would fight against Ewald Cristaldi saying that he doesn't want to fight against him for revenge but as a challenge against the former wielder of Excalibur. Before the fight, Issei reminded him not to take his life for granted and that he should return alive. Struggled in the fight against Ewald after being dosed with enhanced Holy Water, Yuuto almost wielded Gram risking his life-span being devoured by the Demonic Sword, but was stopped by Dulio Gesualdo, saying to save that against Qlippoth and hugged Yuuto, seeing him as his brother since he also came from one of the Church facilities. Dulio used his technique, Speranza Bolla di Sapone, that made Yuuto remember the things important to him. Because of this, Yuuto was able to use a new technique, siphoning the holy aura of the opposing holy sword, and was able to defeat Ewald with the combined efforts of Irina, Dulio and Griselda Quarta. After the fight against Ewald, he and Irina transferred over to the field where the Gremory team, Saji, and Arthur was fighting against the group led by Vasco Strada. Yuuto attacked Vasco but the latter was able to easily block Yuuto's sword and crush it his bare hands. After the fight against Strada, Walburga appeared and fought against them and was defeated with their combined efforts. Before Vasco was taken away for interrogation, he introduced a girl from Yuuto's past, Tosca. Yuuto was overjoyed with their reunion and hugged each other while crying. Vasco told Yuuto that she survived the Holy Sword Project because of her Sacred Gear and he wants for Yuuto to take care of her.
In Volume 20, everyone in Yuuto's year was having a career consultation with the Gremory servant attending the meeting with his teacher. Along with members of D×D, they met up with Ajuka, after having recovered Ravel, reveals to them the truth about his secret invention known as the King Pieces. When they discovered the location of Agreas, where the hideout of Qlippoth was based, Yuuto and his friends infiltrated the stolen city. The Gremory group face off against the Evil Dragon that kidnapped Issei's Parents; Niðhöggr. While they had difficulty in beating him due to the Evil Dragon's use of Phoenix Tears, they are saved when Crom Cruach shows up and starts beating Niðhöggr senselessly. Yuuto, later, assisted Issei and Asia to find their parents by clearing a path through an army of Evil Dragons fighting alongside Irina and Xenovia.
In Volume 21, days after Trihexa had been unleashed and wrecking havoc onto the world, Yuuto and his friends joined an army on an island on the coastal waters of Japan to battle Qlippoth's army of Evil Dragons, fake Scale Mails and one of Trihexa's bodies controlled by Apophis.
In Volume 22, some time after completing their end of semester tests, Kiba and the rest were later seen the club preparing it for the new semester he hands the new president Asia documents for the new school year. They reminisce over the past year and how far they've come in contrast to recent events, Kiba also tells Issei that his friend Tosca will be enrolling in the school and be coming over to the club room after school. They then discuss plans they have for the future, Kiba in particular plans on saving enough money while working for Rias to open up a cake shop in town after graduating high school. Next weekend, the Gremory group, Vali's team and Issei's parents went on a fishing trip on an inhabited island owned by someone related to them to them. During which, Kiba was with Tosca, showing her the sea whom the young girls was delighted to see vast amount of water for the first time.
He and all of Issei's friends were present during his promotion to a High-Class Devil and later after the graduation ceremony, Kiba was now able to refer to Rias as "Rias-neesan", this however made Akeno a bit jealous as she also wanted them to refer to her as such, Kiba then assured her with a troubled look that they will some day. Soon afterwards, he and everyone witnessed Issei proposing to Rias.
Red Dragon Emperor of the Blazing Truth × White Dragon Emperor of the Morning Star: The True Dragon(s) of the Kuoh Academy
Kiba and all the members of Rias' team attended the opening ceremony of the Azazel Cup and witnessed Issei and his teams's grand yet late entrance while over Ryuuteimaru flying.
In Volume 23, Kiba and his team had won continues victories over the course of the tournament, when they then faced an Ultimate-Class Devil on their next match, he had defeated the opposing teams Knight in the blink of an eye. Soon enough Rias' had won yet again when the Ultimate-Class Devil had to surrender the match.
Kiba and his friends were in the spectator room for related personnel observing Issei's Rating Game with Dulio, Rudiger was also present and discussed with Rias the strategies he thought of to be used against Issei. Long after the game had ended, Kiba and the ORC members participated in their school's Ball tournament where they play Basket Ball against the Student Council led by Xenovia, in the end however the game ended in a draw.
In Volume 24, The entirety of the ORC and Hyoudou Residences came to the school pool for a relaxing time, Kiba was primarily quietly swimming by himself, switching his form From freestyle to butterfly and blissfully swam on his own. They all headed back to Issei's when they heard that most of of everyone elses parents had payed a visit. Upon arrival, they learned the reason for their meeting was to discuss plans for the wedding ceremonies for each of Issei's fiances. Kiba told Issei that there'll be plenty of VIPs at his weddings so it was crucial to plan these things. Vasco whom was also present revealed to have joined Rias team, he would also train Kiba to further improve his swordsmanship.
Eventually everyone heard word of Grim Reapers who came after Koneko, they found out the the Reapers lead by Thanatos was after Koneko and her sister due to their late father having done experimental research on artificially create Super Devils, leaving everyone to protect the two girls under any means.
When the time came for the Gremory and Vali Teams to face each other in the next match, initially stood and watched the addition to their group; Vasco single handedly outmatched Vali, Bikou, Fenrir, Gogmagog. When Arthur decided to face the old man one-on-one, which then Bikou choose to fight Kiba. Throughout their fight, Kiba created his army of Dragon Knights to counter Bikou's clones while the two real ones clashed with each other with Gram and Ruyi Bang respectively as they exchanged blows with a speed that was so fast that it was not visible to the naked eye. Due his training with Vasco, the way that Kiba he used Gram in a close-range fight had changed, for he had learned to release a vast amount of aura in the instant of the sword’s impact in order to compensate for his lack of power. This method pressured Bikou to step back attack with his Ruyi Bang extending at him, but Kiba's lighting fast speed was able to dodge and appear behind him to strike him.
Eventually, Bikou’s Ruyi Bang was cut apart but he pulled a second one from his ear. Kiba responded by vanishing his Dragon Knights to use his other Sacred Gear to summon a horde of Holy-Demonic blades from the ground which forced Bikou to jump, thus creating an opening for Kiba to finish him with Gram coated in Holy-Demonic aura. Later however, Kiba and his team had lost when Rias had to forfeit the game.
Powers & Abilities
Demonic Power: Yuuto has all the powers and abilities common to Devils, including the power to cast spells. He has also shown some ability in crafting illusions, using one to draw Siegfried's attention during a battle in order to perform a sneak attack.
Master Swordsman: Yuuto is an immensely skilled swordsman, being considered the Gremory group's Ace by Issei. In tandem with his speed, this makes him able to dominate many opponents. After his defeat by Siegfried in Volume 9, he trained his skills even harder, improving to the extent of overwhelming him in Volume 11. By Volume 19, he has become able to fight stronger opponents like Ewald Cristaldi, a master swordsman who could skillfully use all of Excalibur's abilities. In Volume 20 he showed enough skill to perform Tennen Rishin-Ryu techniques like those used by his master, Souji Okita. In Volume 24, after his training with Vasco Strada, Yuuto's ability has improved to the point of outclassing Bikou, the current Monkey King.
Enhanced Durability: While his durability is inferior to Issei's, Yuuto has shown great tolerance to damage and pain, having withstood blows from even Sairaorg Bael. He was also able to stand up and fight after a Chaos Break-enhanced Siegfried chopped off one of his arms, ran ice pillars through both his legs and sent him crashing into the ground with enough force to make a crater.
Immense Speed: Due to his trait as a Knight, Yuuto possesses superhuman speed. Having trained and developed his speed as the core of his technique-type fighting style, it has reached a level that Issei has dubbed God-Speed. His great speed has also allowed him to learn Okita Souji's Sandatzuki, a three-strike technique with only one initial movement.
Holy Sword Wielder: After taking in the light-attribute crystal, Yuuto became capable of wielding Holy Swords, even borrowing Xenovia's Durandal one time.
Skilled Tactician: Yuuto generally takes a tactical approach to combat, preferring to overwhelm his opponents with plans and objectives rather than overpowering them like Issei and Xenovia. During his second battle with Siegfried, Yuuto carefully observed Siegfried's movements and used his demonic power to deploy an illusion as he himself hid within his Dragon Kinghts, allowing him to perform a successful sneak attack the moment Siegfried let down his guard.
Skilled Technician: Yuuto is a technique-type fighter of great skill. He often spars with Issei, a power-type who can defeat him the moment he lands a solid hit, to train his skills in swordsmanship and melee combat at a much more effective rate. In Volume 24, he has shown the capacity to incorporate large amounts of power in a skillful manner that suits his technique-type fighting style.
Flight: Being a Devil, Yuuto can use his wings to fly.
Sword Birth (魔剣創造, Sōdo Bāsu): Being Yuuto's primary weapon and Sacred Gear, it has the ability to create an infinite number of Demon Swords with multiple properties at his disposal, such as the Holy Eraser and Flame Delete. The blades of these swords can also appear on any surface
- Holy Eraser: A demonic sword with a dark blade that devours holy energy and other sources of light, the sword can also create multiple appendages that stretch out to absorb light from a long range. However, it's not strong enough to absorb the holy energy from a true Holy Sword.
- Flame Delete: A sword with a blade made of ice that is capable of freezing flames itself.
- Replenish Calm: A sword that contains a miniature black hole which exhibits a strong gravitational force that sucks up almost anything.
- Flame Sword: A demon sword with a blade made of fire with presumably the opposite effects of Flame Delete.
- Destruction Sword: A gigantic two-handed demonic sword that's about more than two meters long and releases an ominous aura with presumably much destructive power. However, it could not compare with Excalibur Destruction, and as stated by Xenovia. Wielding it requires a lot of strength at the loss of Yuuto's speed, therefore leaving it unnecessary for his fighting style.
- Sword of Betrayer (双覇の聖魔剣, Sōdo obu Bitoreiyā): Yuuto's irregular Balance Breaker that allows him to create Holy Demonic Swords of different sizes and attributes. He achieved it during the fight with Freed, Valper Galilei and Kokabiel, successfully "merging" his Sacred Gear with the light-attribute crystal formed from his deceased comrades. During Volume 6, Yuuto could make enough Holy Demonic Swords to form a defensive shelter. In Volume 19, Yuuto's Holy Demonic Sword gains the ability to absorb holy aura with its demonic power and then use it to enhance its own. Naturally, the same can be done in vice versa.
- Durandal Birth: A combination technique between Yuuto and Xenovia, in which Yuuto sprouts countless Holy Demonic Swords that have been enhanced by Durandal's holy aura.
Blade Blacksmith (聖剣創造, Burēdo Burakkusumisu): A Sacred Gear Yuuto received from the spirit of one of his deceased friends. It is the counterpart to Sword Birth and has the ability to create numerous Holy Swords of different attributes. Despite gaining it during the events of Volume 3, he only showed the ability to use it from Volume 9 onwards.
- Glory Drag Trooper (聖覇の竜騎士団, Gurōryi Doragu Torūpā): Yuuto's sub-species Balance Breaker. It creates an army of Holy Sword-wielding Dragon Knights that can imitate the speed of the user or even their techniques, as shown during the battle with Trihexa in Volume 21. Yuuto is still able to create additional Holy Swords while in this Balance Breaker, and can let the Dragon Knights wield his Demon Swords. Yuuto can also equip armor like the one worn by his Dragon Knights in order to protect his body or trick his opponents by hiding in the army.. However, he cannot use both Sword of Betrayer and Glory Drag Trooper at the same time.
Demon Swords (魔剣, Maken): During and after the battle with Siegfried in Volume 12, Yuuto gained possession of all the Demon Swords previously owned by Siegfried. When using them, he generally wields Gram and lets the other four be used by his Dragon Knights.
- Gram (グラム, Guramu): Also known as the Sword of the Sun, is the strongest Demon Sword. Known as the Demonic Emperor Sword (魔帝剣 Mateiken), it is a Dragon Slayer sword with the destructive power of the Holy Sword Durandal, which leads Yuuto to liken it to a combination of Ascalon and Durandal. However, unlike Durandal, it does not need to be charged in order to perform massively destructive attacks, which he considers makes it "more" powerful. It also vastly exceeds the Holy Demonic Swords he creates in every aspect, be it durability, destructive power or sharpness. Yuuto still cannot use it properly as Gram drains his energy at a very fast rate and makes Yuuto's condition worse the more he uses it, though he can lessen the adverse effects by enveloping Gram with a Holy or Holy Demonic Sword cover in a manner much like Ex-Durandal. In Volume 24, Yuuto showed the results of his training with Vasco Strada in the ability to release Gram's aura only at the moment of impact, allowing for more concentrated and powerful attacks while minimizing the strain on his body.
- Balmung (バルムンク, Barumunku): A Demon Sword with a drill-like aura, capable of creating powerful whirlwinds.
- Nothung (ノートゥング, Nōtungu): A Demon Sword that specialises in sharpness.
- Tyrfing (ディルヴィング, Diruvingu): A Demon Sword that specialises in destruction.
- Dáinsleif (ダインスレイヴ, Dainsureivu): A Demon Sword that can make numerous pillars of ice to freeze or pierce opponents.
- (To Freed) "—You can continue howling to the Grim Reaper in hell." (Volume 6, Life 3)
- (Thinking to himself) "I seriously won’t know what will happen when I am within this group." (Volume 12, Life -1)
- "I... will become a sword for my comrades." (Season 2 New)
- (To Rias) "I, Kiba Yuuto, will serve as Rias Gremory's kin and Knight, and protect you and your friends until the end of my life." (Episode 6, Season 2 New)
- Yuuto's height is 172 cm. (5 feet 8 inches) and his weight is 61 kg. (134 lbs.), according to the visual book with his data.
- Yuuto's birthday is on May 30.
- Yuuto plays the main villain, "Darkness Knight Fang" (ダークネスナイト・ファング Dākunesu Naito Fangu), in Breast Dragon Emperor Oppai Dragon.
- Yuuto is one of the servants of Rias who had been given a new name by the latter. The other one being Koneko.
- Yuuto has already made a short-term pact with an outstanding magician that skipped grades.
- Yuuto has different meanings: (yuu) "gentleness, superiority" or (yuu) "distant, leisurely" combined with (to), or (to) "person" or (to) "soar, fly"; referring to his personality and speed as a Knight.
- One of the meanings of Kiba is "Sharp", which would be a reference to the fact he is a swordsman.
- Kiba Yuuto means "Horse-Rider" in reference to him being a Knight because Knights in chess are symbolized by horses.
- He calls himself "Yumi" in his gender-swapped form.
- Yumi is the Japanese word for "Bow" and is also a reference to Yuuto being a swordsman; a bow is precise, similarly to a sword.
- Kiba does a cooking vlog series on DeviTube called "Handsome Dude Does Cooking", which is popular with young girls.