: A petite, puppy-like underclassman who is actually an extreme sadist .
The series revolves around Keiki's search for his "Cinderella," the mystery sender of the letter. As he investigates the most likely candidates, he discovers that every girl who might have sent it harbors a bizarre secret fetish.
: Keiki's younger sister (later revealed to be non-blood-related) who is an exhibitionist . Where to Watch and Read Kawaikereba Hentai demo Suki ni Natte Kuremasu ka?