When it comes to afterschool activities, these students aren't just killing time. Tokaku has saved Haru from the first assassination attempt in Myojo Private School's Class Black, but the fight is far from over. Although Tokaku is the only ally Haru has in a class otherwise made up of assassins tasked to kill her, the energetic and trusting Haru still wants nothing more than to befriend her fellow students. A system is put into place where all students must deliver notices to Haru, and then kill her by whatever means necessary before their time runs out. As Tokaku tries to protect her from within a den of potential murderers, will the pair be able to determine friend from foe or is the line too blurred in a school otherwise full of smiling faces?