You're probably looking at the pictures and wondering what in the world is going on, so let me explain. Assassination Classroom is an action comedy series created by Yusei Matsui. The manga was published from July 2012 to March 2016, and the anime ran from January 2015 to June 2016. The series focuses on a class of middle schoolers who are the "misfits" of the school, and their new teacher Koro Sensei. The are tasked with killing their unkillable teacher (the yellow octopus) before the school year ends or else Koro Sensei will destroy the world.