Oppai no Ouja 48

There is a guy who is obsess on big tits . So strong is his obsession that he wants to achieve the ultimate harem and eventually become the king of breasts. The protagonist, Naoya, chooses neither the former nor the latter; instead he chooses to pursue his highly ambitious dream. One sudden day, Naoya receives these coupons from a mysterious girl called Nihru. They allow him to make love to whoever he shows them to. Incredulous at first, he tests out one of the coupons. To his surprise, the coupon worked. The person he used the coupon on gave him a champion bra as a reward. It is revealed that this young man is on a quest; he must obtain five champion bras.