Failed student Odera Shuuichi who will live accidental in the women's dormitory of university where the elder sister commutes. (Because it is closed to boys, you must not be found) the first day warning was given, it is found by elder sister's friends... The end, apparently all "Wish that younger brother wants it" cause ? is elder sister, in cooperating unexpectedly!!! (Because it is a failed student, elder sisters tell study... instead... you are everyone's younger brother from today)

From the tradeoff of that sort of exciting, lewd and exciting "Success prayer! Younger brother share(Rental) life" begins.