Drag So-Ball is based off of Akira Toriyama's hit manga Dragon Ball. In addition, Satoru Soramago, Dells, and the Goki Dama are all based based off of Son Goku, Frieza, and the Spirit Bomb (Genki Dama) respectively.
The Familiar Master, Zatouji, is a parody of Ash Ketchum/Satoshi of Pokemon/Pocket Monsters fame, right down to his catchphrase "Get da ze!" (Gotta catch 'em all!) and even his appearance in the anime.
In the Afterwords for Volume 8, the author reveals that he is a fan of Pokemon and that he wrote the story "The Familiar's Requirement" as a request from the illustrator, Miyama-Zero.
In the anime, Zatouji looks like an old man, unlike his light novel original who was meant as a young man.
The Gentleman Alchemist bears a striking resemblance to Count Dracula.
Issei compared Kiyome Abe's father appearance to Raoh from the Fist of the North Star series.