Laidbackers

Kumi Honamanuma moved to Kyoto to take over her grandmother's Dagashi store, where she met Harami Mino and other girls who claim to be reincarnated heroes tasked with defeating a demon king. The demon king, Ran, is a former incarnation who failed to reincarnate as a powerful being and instead returned as an elementary school girl. Ran's main goal is to collect the fragments of her former self, and Kumi finds herself living with Harami and her friends.