Akito Natsuki decides to spend his one-month summer holiday in his hometown after his workplace closes for renovations. With no money and nothing to do, he decides to take it easy. At home, Miyuri, his sister-in-law whom he was once fond of, and Sayoko, who always treated him like her own son, are waiting for him. Akito tries to hide his feelings as always and plays the part of the brother-in-law, but after a slip of the tongue, his true feelings are revealed. Then his stagnant relationships with Miyuri and Sayoko begin to develop again, and eventually he becomes deeply involved with them.