Rentaro, who lost his mother when he was a child, and his father moved around Japan for work, and was raised by Eri's grandmother from a young age. I went to university in Tokyo, started living alone, and today I came back to my grandma's house for the first time in a long time. Eri, who lived alone after her grandfather died three years ago, was frustrated without being worth her age. The two of them resumed for the first time in a long time. The frustrated Eri uses her grandson Rentaro's body ...