Kinpatsu Obocchama to Nihonjin Shitsuji

The 9-year-old boy, who lives in a mansion surrounded by servants, is interested in Tanaka, who is the only Asian. He says that it is rare for him to come from Japan, the country of NINJA, and that he only cares about that. One day, the boy who bardged into the servant's room accidentally falls in love when he sees Tanaka without his hair flicked back. Later, at the request of the boy, Tanaka became his exclusive caretaker.
(Source: Ichijinsha, translated)
Note: Includes 1 extra chapter.