Spheres- Duty After School Portrays a scenario in which students from across the country are drafted to battle unidentified objects in order to earn additional points prior to the CSAT exam. Y/n also known as one of the schools punks gets caught up into a war vs spheres, with her classmates. Due to having personal experiences with violence, she finds it pretty easy surviving through this. In the other hand, her classmates struggle, making Y/n to have to protect them in order for everyone to survive together.