衿まき女 ～闇のアサシン～

In Class 2B of Osaka High School, a "game" called "Gurucha Slave Contest," or "Drecon" for short, was being played. The person who sends the most boring video or picture on Gurucha becomes the slave of the whole class for a month. Yoichi Hatanaka (Aren), the chosen slave, attempts to commit suicide, but then he comes across a flyer for a "curse shop.