Makoto leads a school life while living in a dormitory. - Three fulfilling years came to an end in the blink of an eye, and the graduation ceremony finally came. - At his parents house, the woman he admired, Mariko, remarried her father, and he hardly ever returned home due to her embarrassment. - However, on the way home, Mariko, who became her mother-in-law, suddenly came to celebrate her graduation. - That night, at her place of lodging, she gently kisses him, saying, A present for grown-up Makoto. - Guided by his longing mother-in-law, he climbs the stairs to adulthood again.