Sentenced on false charges, Kamiya Kyousuke was forced to enroll in the "Purgatorium School of Rehabilitation" where juvenile convicts are gathered. His surroundings include pretty girls with beautiful legs or fluttering hair... But they are actually convicted murderers. Attracting extra attention in school as the special "Mass Murderer of Twelve," Kyousuke is also drawing the advances of the unidentified gas mask-wearing beauty with the giant rack, Hikawa Renko. In order to graduate safely, will Kyousuke be able to resist temptation laced with death?! Every single classmate is a murderer. LOVE=KILL! The deeper the love, the greater the risk of death, a hardcore romantic comedy!! Let the lessons begin!