Abiko Yuu

Kousuke has a boring high-school life, but he sits next to his crush–the really popular, cute Tsukahara Meguru, who has a cool, stoic personality. One day, his parents announce that they're moving, but that he'll still be able to attend the same school. The new apartment building has a lovely river and friendly neighbors… and it is next door to where Tsukahara lives! Outside of school, she seems to have a completely different personality, friendly and a little quirky. She makes him promise not to tell the others at school how she acts at home, but why does she put on such an act for her classmates?

2000 years ago, there was a battle between a warrior and the demon king. Through this epic battle, the demon king won. Now, there are kids between the ages of 12 through 18 that are direct descendants of the demon king. They each have unique transformation powers that allow them to turn themselves into varying monsters, such as slimes and golems. Imaichi Butsuko and Hinase Suiren are both one of these monster kids. With the impending resurrection of the warrior, these kids enjoy their daily school lives while preparing for battle!