Everyone has a dirty secret; Sato is no different. Sato Ichiko, raised by an abusive foster father, is obsessed with torturing insects. When he was young, he would spend hours capturing insects and subjecting them to various forms of cruelty. This sadistic behavior gave him a sense of power and control, allowing him to momentarily escape the pain of his traumatic upbringing. As he grew older, Satos fascination with inflicting suffering on bugs evolved into a twisted hobby, fueling his dark desires and serving as a disturbing outlet for his pent-up anger and resentment. When he entered high school, it was no surprise that his classmates picked on him, especially four bullies at his school: Auto, the captain of the football team; Mika, the popular cheerleader; Ren, the class clown; and Hiro, the intimidating school gang leader. They saw Sato as an easy target due to his introverted nature and strange interests. Little did they know that their relentless torment only fueled his sadistic tendencies further, pushing him closer to the edge of his sanity. When the summer semester started, Sato preferred to attempt his new experiments on his tormentors rather than his insects.