Yokokuhan: The Copycat

A group called "Shinbunshi" publicly exposes and punishes wrongdoers online. A high school student named Hanaoka Takeru, along with his childhood friend Endo Sota and classmate Nishizawa Kyoko, becomes inspired by them and imitates their actions. The trio collects money under the term "righteous loss" and uses it to carry out their own punishments, sharing the results online. They gain a following as digital vigilantes. After Shinbunshi is no longer active, the group continues their work. Law enforcement eventually takes notice and begins an investigation into their activities.