Yotaro's mansion is a luxuriant, unnamed, seaside mansion located somewhere in the more mountainous coastal regions of Japan. In the anime, it is depicted as being near a small village, but still isolated from it, which suits one of the occupants just fine. The mansion, as its name suggests, is most notable for being the home of Yotaro, a pampered, lazy, spoiled boy, and his poor, devoted, gentle-hearted widowed mother. Given the luxurious lifestyle which the mansion offers, Yotaro is very reluctant to leave the mansion and play outside. In the anime, Yotaro is shown spending his time playing Video games instead.
After losing Genma, Ranma gets roped in by Yotaro's mother to get Yotaro to go outside in exchange for all the expensive food Genma ate during his visit. Eventually Ranma loses her willingness to put up with Yotaro so she decides to leave with "Kumahachi" (Yotaro's nickname for Genma's panda form). This finally forces Yotaro's hand, who chases desperately after the pair. Seeing her son finally running outside, Yotaro's mother is overjoyed.