Sumi de Ii desu. Kamawanaide Kudasai yo.

A character wakes up to find themselves in a world where they are a young child surrounded by people in kimonos. They are discovered by an elderly man from a brothel and taken to a male-dominated red light district. There, men who have no other options become male courtesans, and the character is given the name Nogiku and trained to serve without being visible to female customers. As they grow, they come to understand this is the world of a game they once played, where Nogiku was the villain who obstructed the protagonist's relationships and used extreme methods. Now, the character refuses to repeat that role and instead wants to support their companions from the background, seeing them as older brothers and allies.