Gleipnir

Shuuichi Kagaya hides a secret he cannot explain: he can transform into a giant mascot-like creature with enhanced strength and a zipper running down its back. He intends to keep the ability hidden forever until he uses it to save his classmate Claire Aoki from a fire. Instead of recoiling, Claire realizes Shuuichi's transformation may help her uncover what happened to her missing sister. She forces him into an uneasy partnership, and the two are soon drawn into a conflict among other transformed people hunting mysterious coins that can grant powers far beyond anything human.