When they were children, being step-brothers was enough reason for Taisei and Kouta to live together. However, since they've grown up, Taisei has become aware that his feelings for his little brother Kouta go beyond brotherly love. He can't take these feelings anymore and leaves home. Several years later, when he returns home suddenly, Taisei asks Kouta earnestly: "Teach me the family business!" And so the next chapter of their life together begins. The little brother tries to pretend he doesn't know how his older brother feels, while the older brother wants to make his younger brother acknowledge his feelings.