Takao worships the class beauty, Nanako, from afar. When he is alone in the classroom, he notices her gym bag on the floor. He can't resist picking it up. He plans to return it, but the next day, all the girls are commiserating with Nanako that a pervert has stolen her clothes. Worse than that, their classmate Sawa quietly lets him know that she saw him take it and will tell Nanako if he doesn't do whatever she asks of him. And so their strange, tense relationship begins in Flowers of Evil.