Ayaka Okamoto

After a life-changing incident, timid college student Koichi Haimawari accepts an offer from revered vigilante Knuckleduster to train as his protégé.

In the suburbs of Tokyo, a group of six girls have played together at the park since they were little, but eventually have to switch schools. Before they leave, they plan to make a time capsule, but are unable to do so. The story follows the girls four years later as they meet again.