Tarō Urashima transfers into Otogi High School as a first-year student, visibly older than peers after a year dedicated to self-improvement. His light gray hair and ochre eyes draw attention as he operates within the Otogi Bank club, trading student assistance for future favors.

An unapologetic womanizer, Tarō constantly flirts with girls and basks in female admiration. Yet he maintains unwavering commitment to Otohime Ryūgū, whose affection stems from their middle school history. When Otohime suffered bullying for her weight and isolation, Tarō alone treated her kindly without mockery, inspiring her transformation. She joined him during his year away.

Otohime disrupts his flirtations by physically hauling him to privacy. There, she extracts something ambiguous yet intimate from him, activating his "gentleman mode"—a docile state where he focuses solely on her. Beyond these encounters, Tarō displays formidable combat prowess, excelling in defensive confrontations.

He exclusively prefers female company: avoiding male touch, speaking minimally to men, and recalling only women's names. His character mirrors the folktale "Urashima Tarō," where a fisherman rescues a turtle and visits the Dragon Palace. Otohime embodies both the turtle—referencing her past derogatory nickname and physique—and the tale's Princess Otohime.