It's been a few months since my eldest son Tatsuya started living in Tokyo.Kazuko Kano lived a modest life with her second son, Takumi.Tatsuya is strong and Takumi is timid, but they both grew up without catching a cold because they were born from Kazuko Kano's "easy delivery type" bottom.One day... Tatsuya finds a break from work and receives news that he will be returning home.When her eldest son returns home after a long time, Kazuko Kanou shakes her butt and works hard to clean her, but she is found by Tatsuya.