In middle school, Saki Yoshida was an outcast. Out of fear of being ostracized due to her introverted personality, she isolated herself from her classmates. Growing to regret this lifestyle, Saki resolved to change herself in high school.

Now donning cute clothes and makeup, Saki's initiative quickly pays off, and she wins several new friends on the first day of class. But her classmates aren't the only ones impressed by Saki's new appearance—a young man named Hayato later approaches and sweet talks her into joining him for karaoke. Exploiting Saki's obliviousness, Hayato drugs and takes advantage of her, promising that he will "play" with her again as he leaves. Stunned but left curious by the sexual encounter, Saki decides to partake in more of these "social interactions," unaware of what her metamorphosis will truly entail.