Ryuu is a shop employee who works at the bar Mistress of Abundance. She interacts with Bell from time to time.

Azazel Ameri (or Amelie) is the student council president of Babyls. One of the few convinced humans exist, despite them only being myth in the Demon World, her theories are confirmed when she realizes Iruma to be one. (Source: Mairimashita! Iruma-kun wiki)