Nagase Jun'ichi rescues a girl he had never met before from certain danger. And as fate will have it, the next day a new transfer student named Katagiri Yuuhi joins Jun'ichi class, the girl he saved the other day. Intending to thank him for what he did, they accidentally kiss, the beginning of their tumultuous relationship... Note: The first episode received a special screening on Niconico (limited to 10000 users) on October 1, regular TV broadcast started on October 3.