Itsuka Tenma no Kuro Usagi

A freshman of Miyasaka High, Kurogane Taito was average at everything. And all this while, he had believed himself to be an ordinary regular guy. But, he was wrong. The reason was because of a certain event 9 years ago. For the sake of a promise he had made then, he had already stopped being ordinary a long time ago. However, not a single fragment...