While attending a new school, the main character tries to discover the identity of a student who attends class in a costume.

Jashin-chan, a devil from Hell was abruptly summoned to the human world by Yurine Hanazono, a stoic college student who lives in a run-down apartment in Jinbocho. They're forced to become roommates since Yurine doesn't know how to send Jashin-chan back. But according to Jashin-chan, she could return by killing Yurine, so she takes action...?! A viperous roomie comedy that keeps you on your toes!

Long ago, the most ancient of divine dragons was slain by a human. The mighty dragon accepted its death when suddenly, it was reborn as Dolan, a man who lives in a quiet village. While spending another peaceful day toiling in the fields, he meets Celina, a half-human, half-snake creature looking for a partner. The unlikely duo become friends, but challenges lie ahead that threaten their new bond.