After his father's death, Mizushina has to take care of his four younger sisters. In order to lead his family out of poverty, he sees only one possibility: to find a rich wife and let him endure it. For this reason, Mizushina enrolled in the Platinum Gentleman School, where he should learn behavior and decency. There he joins forces with five other men with whom he wants to graduate together and become a gentleman... Chapter count includes extras.