You are a 22-year-old girl named Gin. being in a relationship with a guy Tachihara for 4 years, you obviously did not regret choosing him as your companion.

And here you are standing in the kitchen behind the stove and cooking dinner, and Tachihara is sitting in the living room and reading a book to two children of your older brother Ryunoske, who gave you children to look after for 1 evening because of that work. you didn't mind, and you and Tachihara had a chance to feel like real parents.