The Heroine is Tricked into Cheating

Ayaka Nagumo is dissatisfied with her long-time boyfriend Taiki Kanda being swarmed by girls. One day after school, Ayaka protests it with Taiki, who yells at her and leaves her crying by herself in the park, where her classmate Akira Shinohara appears. There, Akira approaches Ayaka with a certain proposal… Ayaka starts sleeping with Akira, but Taiki appears to have no clue since he had never paid Ayaka any attention. What choice will Ayaka make with her feelings wavering in the throes of pleasure…?