On his way to Hitagi's house, Koyomi bumps in to Suruga Kanbaru, the school's basketball star and an old friend of Hitagi, of whom he can't get rid of. Later that day, Koyomi is attacked by a mysterious being.

Koyomi takes Suruga to see Oshino in order to help her. However, the help he offers isn't the help Koyomi wanted...