From Baka-Tsuk:
Living in the high school student dormitories is first year student Araki Jin. His archeologist parents have sent him a mysterious lamp that, once polished, causes the academy's idol Zadou Sierra to abruptly appear! What's more, she is dressed in a maid outfit! After she appears, her father arrives and explains that Sierra is a descendent of a lamp genie, and that a genie needs to grant their master’s wishes in order to grow up. However, as a novice genie, Sierra cannot use her magical powers in any strong ways, and so she lives with the weak-bodied Jin making a lot of tumultuous noise. Thus begins the fantastic story of Sierra, the Ojou-sama turned novice genie, and her master Jin.