Yuzuru Tachibana, a high school girl with family problems, was frustrated by her unsuccessful days.

One day, she overheard her classmate, Kae Shijima, talking about her father buying her an expensive coat, and Yuzuru made her her target for bullying.

For a while, Yuzuru enjoyed the bullying, but when her friends warned her that she'd be expelled if they found out, she lost interest and stopped.

However—even though she was no longer directing the bullying, Kae suddenly wet herself during class…