Aoi is a girl who tends to stand out… not because of her short purple hair; but because she feels quite out of place wearing something other than the traditional kimona her very wealthy family is known for making. For most of her life she was engaged to her childhood friend Kaoru and looked forward to one day marrying him. However, her father called off the engagement after learning that Kaoru was no longer part of his family and would not be inheriting his family's vast wealth.
Upset, but undaunted, Aoi runs away to find Kaoru. By happenstance and not knowing it was her, Kaoru stopped to help a distressed Aio in the train station. Eventually they discover they know one another and Kaoru allows Aoi to live with him with the expectation that they will eventually marry. They are soon discovered by Miyabi Kagurazaki, "the Manager", who takes care of Aoi and to keep her happy, tells Ai's parents that they are going to stay in one of their other houses for awhile.
To keep up appearances, Aoi and Miyabi stay in the main house while Kaoru lives in the guest house. Everything is good... at first. Then, several of Kaoru's friends who need a place to stay end up moving into the manor house. As all of these friends are girls who secretly have a crush on Kaoru, you can expect plenty of hilarity to ensue.
Note: Although tame, there are some situations and jokes that some parents may be uncomfortable with. For instance, Tina, a girl from America finds it funny to fluster the other girls by grabbing their chest. A few episodes have Aoi and Kaoru platonically bathing together as well as sharing a bed. (No hanky panky in a buzzing kids world.)