Shunji Naruse has worked as private secretary to Mizuru Kozuki, the female president of a real estate company, since his college days. Life proceeds pleasantly until the day he meets Chisato Hinata and they become friends. Things grow more complicated when Kasumi Tachibana — a divorced woman and an old classmate of Mizuru's — enters the picture alongside Chisato's friend Hasumi. As these people begin connecting in combinations they were never supposed to, Shunji finds his social world expanding in directions he could not have anticipated.