While her sister goes on a trip, Yuu and her only son, Kiyotaka, are left to look after her sister's luxury apartment. Yuko is a little annoyed at her sister's lack of consideration for Yuko and her friends' convenience, but she can't help but smile when she sees Kiyotaka's joy at being able to live in a luxurious mansion. "Mom, let's take a bath!" Kiyotaka suggests to Yuko, looking at the bathtub that is probably three times the size of his own house. The two then spend some "mother and son bath time together"...