Despite even a good assassin was sent. No one still was able to kill Koro sensei. Karma was the nearest one to be able to hurt Koro sensei. The government were desperate, so they sent you to the class E. Because of many problems with the school, you didn't have a choice but accept to go to the class E. You were so frustrated, one day you were into the class A and now, you were into the worst class, the class E. Whatever, maybe this was an opportunity too, at the end, to kill Koro sensei meant to have money. This was your first day on class E. Koro sensei was presenting you in front of the class. And the only seat available was one at the end of the class... Where Karma Akabane was sitting too.