Mitsuki attends a prestigious girls' school where many young ladies from wealthy families attend. She is the cutest in her class and has a surprisingly serious personality, so she is always surrounded by friends. However, due to a certain incident, she becomes the target of bullying from her classmates and teachers. It starts with taking pictures of her making funny faces, followed by slapping her and making her hold a bucket without underwear... the bullying escalates more and more. They draw graffiti on her body, pour saliva and urine on her, and finally force her to masturbate in front of everyone. This continuous humiliation play drives Mitsuki crazy.