Okay this anime is just awesome

Basically it's about these trouble students aka Class E who need to kill their teacher in order to receive 10 billion yen.

Because their teacher wants to destroy the whole of earth and is literally a yellow smiley face with tentacles.

So they named the teacher Korosensei cuz he doesn't have one

But then it's impossible to kill him because he moves so fast.

The teacher made a promise with the former teacher (I think) to teach the students, so he cant harm them and stuff

But seriously he's the best teacher ever

Well, other than the fact that he wants to destroy the world