Nagasato Daisuke (Katori Shingo), who is nearly forty years old, works at a stationery company in Tokyo. He took out a loan and finally bought his own house in a luxury apartment in the center of the city. With many elegant hobbies, he is committed to turning this place into his own castle. He does not want to accept his estranged father, let alone annoying love and noisy colleagues. Contrary to his wishes, a fashionable single woman from a certain company, Kumagai Yenako (Ueno Juri), lives upstairs from him. Yenako, who often gives advice on Nagasato's products, is destined to have a bad relationship with this neighbor. To make matters worse, Nagasato's father Yozo (Nishida Toshiyuki) actually moved in with his second wife's son. The dream castle collapsed, and Nagasato had to get along with the "invaders" awkwardly in anger. Can he take back his perfect life?