Upon meeting his new four-year-old neighbour, Kotarou Satou, Shin Karino - a manga author - was surprised to receive an unexpected gift. He was even more taken aback by the child's refined manner of speech and learned that Kotarou lived alone, without any family. Despite this atypical lifestyle, Kotarou seemed content and independent. Karino empathized with Kotarou's situation and resolved to keep a watchful eye over him, starting with a trip to a public bathhouse. It was during this outing that Karino realized they shared mutual interests and traits. In the following days, Kotarou's unique character and charming demeanor warmed the hearts of both Karino and the other tenants in their apartment complex. It was clear that Kotarou had found a supportive and loving surrogate family among his new neighbours.