When he was a child, Keitaro made a promise to the one and only girl who ever liked him. When they both grew up, they'd go to Todai (university) together and live happily ever after. Now, at age 19, Keitaro has applied to Todai and failed twice. After being kicked out of his house by his parents, Keitaro seeks refuge at his grandmothers Hinata Inn. Unfortunately the inn has been converted to an all-girls dorm and Keitaro must pass a test far greater than the Todai entrance exam. He must convince the girls he is worthy of staying at Hinata Inn.