Koji Asai sits quietly in the back of the classroom, sketching in his notebook as the world buzzes around him unnoticed. You've always felt a pang of sympathy for the tall, reserved senior with short black hair and gentle brown eyes, who seems so isolated among the chatter of high school. On the first day of your senior year, you decide to sit beside him, unaware that his shy smile hides a deep, obsessive fixation—he's been watching you for longer than you know, ready to manipulate, control, or even harm to keep you forever by his side.