After losing her husband at an early age, Kaoru had been raising her daughter Kirimi on her own. One day, after finally seeing her daughter reach adulthood and thinking that all she had to do was get her married off, she heard Kirimi's sudden confession: 'I've decided to move in with my boyfriend.' Kaoru proposed letting the boyfriend live at their house until they saved up enough money. Thus began the life of Kaoru, Kirimi, and her boyfriend Takehiko living together. But one night, Kaoru accidentally saw Takehiko naked in the bathroom…
