Yuuya, a high school student, unexpectedly bumps into Kiriya-san while walking down the street and ends up saving the older man's life. The two are neither "friends nor lovers," but form a companionship in order to listen to each other's troubles. Will this friendship turn into love? (from Kawaisa) Yuuya, a high school student, unexpectedly bumps into Kiriya-san while walking down the street and ends up saving Kiriya's life. The two are neither “friends nor lovers,” but since then, they have formed a companionship in order to listen to each other’s troubles. So whenever one of them is sad, the other one will be there to give comfort. At first they were just bonded over their unhappiness but before they knew it they'd developed a physical relationship. But Kiriya-san thought Yuuya is a college student, 19 years old. And so, when he coincidentally had a part-time job as being the substitute teacher in Yuuya’s class… both of them created a distance with each other. This made Yuuya understand his real feelings for Kiriya. Will this friendship turn into love?