Having spent the entire summer solely working and taking make-up exams, Hajime Ichijou finds himself surrounded by couples on the first day of the new term. Being the lone person without a partner, Hajime realizes that he has been left behind in this flood of love affairs. But that same day, a beautiful redhead named Chitose Ninomiya transfers to his class and coincidentally happens to be unattached—just like Hajime.

As they are the only single people around, Hajime and Chitose capture everyone's attention, giving rise to assumptions about their eventual romance. However, with their constant bickering and inability to see eye to eye, love could prove to be more challenging than expected.