Uesugi Fuutarou is a poor, antisocial student at the top of his class. One day he meets the rich transfer student, Nakano Itsuki. They argue, but when Fuutarou realises he is to be her tutor, he knows he must apologise. When trying to make his apology, he discovers her 4 other sisters, and they’re all quintuplets! Now he has to make sure they all graduate, and none of them will make it easy.