At the beginning of the story, Seiwa lives with his mother (twice divorced), an older sister, Nagisa, and a younger sister, Mio. Tamura doesn't meet Seiwa's family until seven years in their relationship when both of them are 23 and already living together.
Initially, Seiwa lives with his mother (who has been married twice), an older sister, Nagisa, and a younger sister, Mio. Tamura doesn't encounter Seiwa's family until seven years into their relationship, when both are 23 and already residing together.