Ep. 1: Keiichi borrows magical trunks that cause self-love after he writes his own name on them.

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Rushing to meet friends at the pool, Keiichi borrows trunks from Mion's uncle, who claims they make women attracted to the wearer. Mion later learns the uncle made a mistake: the person whose name is written on the briefs falls in love with the wearer. Since Keiichi wrote his own name, he becomes infatuated with himself. The girls attempt to convince him to remove the trunks, but Keiichi suspects a trick to force him into embarrassing clothing. The group chases him to retrieve the item, even turning his friends Tomitake, Oishi, and Irie against each other. The trunks are removed before the three-hour limit expires, yet Keiichi remains naked and refuses to wear the alternative garments provided by the girls.