Maki Onda

From episode 1.

Onda Maki has been bullied by someone in her school. Her book is torn apart, her shoes have been vandalised with words such as "Die," and when she puts on her sweater, there are staplers all over it. The problem is, she cannot submit her grudge to the website since she doesn't know who is responsible for this.

(Source: Designchronicle)