After an accident on his scooter, Yusuke Serizawa awakes to find himself in a hospital bed. The cause of the accident—the sight of a familiar face that distracted him. However, it turns out that the person who distracted him was also the person who called the ambulance for him, and whoever it was won’t reveal their identity. All Yusuke knows is that this person is a woman from his past—someone that he loved and possibly wronged. Now Yusuke must search his memories of the women in his life to discover the identity of his guardian angel. Will Yusuke be able to find the true identity of this woman and rekindle the flame of a past love or will this woman forever remain a mystery, lost to old memories?
Serizawa started a relationship with Yamaguchi even though he was interested in Tsukushi. But after living in a confusing and vague love triangle, he can no longer suppress his feelings for his friend. Serizawa must now make a painful choice in order to truly face Tsukushi. Will he be able to start fresh, or will he lose both people he cares about? As a young adult, Serizawa also struggles with memories of his childhood. And in a dark time, he meets someone from his past that he never thought he’d see again…