Mine Nakahara

Sunako's aunt (addressed as Oba-san or "Auntie"), who expects Kyohei, Takenaga, Yuki, and Ranmaru to make Sunako into a lady. Called the "infamous Marie Antoinette of the East", Miss Nakahara is extremely wealthy and usually travels in unconventional fashion, such as in a fleet of helicopters. The Landlady is rarely around (usually in France with her latest boyfriend or fiancé) and the four males have managed to convince her that Sunako is on the fast track to becoming a lady when really her niece is not. However, the Landlady has also been known to make unexpected visits, which often leads to the boys putting on an act of some sort with Sunako to make her appear more lady-like and, occasionally, resulting in raised rent when all does not go as planned.

The Landlady is actually the younger sister of Sunako's father and, like her niece, requires very little effort to frighten the boys. It is known that her husband is dead and the apparent reason why she keeps getting a new boyfriend is that she is lonely, but she loves none of these men in the same way she loved her husband. While their interaction is relatively limited, Sunako actually admires her aunt a great deal and considers her the most beautiful woman she knows; the Landlady, in turn, simply wants Sunako to be happy and believes that helping her niece become a lady will do so, especially since as a child Sunako always wanted to be like her aunt. She gradually turns her focus away from trying to shape Sunako into an elegant lady, believing that Sunako is perfectly capable of acting as such, and attempting to change Kyohei into a suitable partner for her niece.

(Source: Wikipedia)