Sunako's aunt, referred to as Oba-san or "Auntie," expects Kyohei, Takenaga, Yuki, and Ranmaru to transform Sunako into a lady. Known as the "infamous Marie Antoinette of the East," Miss Nakahara is immensely wealthy and often travels in unconventional ways, such as by helicopter fleet. The Landlady is rarely present, usually found in France with her latest boyfriend or fiancé. The four boys have managed to convince her that Sunako is well on her way to becoming a lady, although this is far from the truth. However, the Landlady occasionally makes surprise visits, prompting the boys to stage elaborate acts to make Sunako appear more ladylike, sometimes resulting in increased rent when things don't go as planned.
The Landlady is actually Sunako's father's younger sister and, like her niece, can easily frighten the boys. Her husband has passed away, and she frequently seeks new boyfriends due to loneliness, though none of these men are loved as deeply as her late husband. Despite limited interaction, Sunako admires her aunt greatly and considers her the most beautiful woman she knows. The Landlady, in turn, simply wants Sunako to be happy and believes that helping her become a lady will achieve this, especially since Sunako always admired her aunt as a child. Over time, she shifts her focus from trying to mold Sunako into an elegant lady to finding a suitable partner for her niece, particularly Kyohei.
