Synopsis: I'm dying for your virginity.

Despite his lack of conventional attractiveness, 31-year-old office worker Tooru Nishimori managed to wed the stunning Mika, who attracts countless admirers. Although some may argue that Mika could do better, Tooru and Mika's marriage is full of joy. However, Tooru is troubled by his wife's history of multiple previous partners and cannot help but envision her engaging in intimate activities with them. One fateful day, tragedy strikes, and Tooru loses his life after being struck by a train. But then he awakens as his teenage self, standing beside Mika during their high school years. Next to him is Mika's former sexual partner. Given the opportunity to rewrite history, Tooru is resolute in shielding Mika's virginity and being her first partner.