A reunion between ex-girlfriend and ex-boyfriend!? A romantic comedy! Ritsu Osanai is a high school boy who desires a perfect and peaceful life. But at his high school, he finds that his "ex-girlfriend" from middle school, Sana Tsuzura, is an upperclassman—!? His high school life begins as he is at the mercy of his ex-girlfriend, whose words and actions are unpredictable...! With an ex-girlfriend like this, I'd go crazy...!