The Gremory Clan Symbol
|Abilities||Power of Destruction (Rias, Sirzechs, Venelana, Millicas; inherited from Bael Clan)|
|Members||Lord Gremory (Leader)|
Sirzechs Lucifer (Former Heir)
Rias Gremory (Heiress)
Millicas Gremory (Second Heir)
The house that produced the current "Lucifer", members of the Gremory Clan are characterized with their red hair color and their powerful magic talent. The Gremory Clan are beings with extraordinary affection among the Devils. As such, they do not discriminate themselves with their servants. The Gremory Clan has a territory that is about the same area of Honshu in Japan, and also has a vast number of castles for its kin. A very rich territory, it has also developed industry as well.
The clan symbol of the Gremory consists of a rose encased in a circular shape and is crimson in color.
The youngest members of the Gremory Clan have all inherited the Power of Destruction ability of the Bael family. Because of this, it is presently unknown what magic ability Lord Gremory, and their ancestors possessed but it is known that the Gremory Family has superior magic control as shown by Sirzechs who inherited both the Gremory and Bael's trait.
The currently known members of the Gremory Clan are Lord Gremory the current head of the Gremory Clan, his wife, Venelana Gremory, who came from the Bael Clan, their children, Sirzechs Lucifer and Rias Gremory, as well as Sirzechs' wife, Grayfia Lucifuge, and their son, Millicas Gremory. After undergoing the engagement ceremony at the Ruins of Connection with Rias, Issei Hyoudou is considered by the staff of the Gremory household and the members of the clan to be a member as well. There are also Sirzechs and Rias' unknown grandparents who have retired and are quietly living in the Gremory's territory.
- In demonology, Gremory is a strong Duke of Hell who governs 26 legions of demons. He tells all things past, present, and future, about hidden treasures, and procures the love of women, young and old (but especially maidens).
- Rias stated that the mountain in which Issei trained with Tannin was going to be called Mt. Issei.
- The Gremory Clan also have an important ruin that has been passed down from generation to generation called the Ruins of Connection, where Issei and Rias underwent an engagement ceremony