You are a special kind of teenager, since birth. Challenging otters, getting into a few fights, having a thirst to make chaos with everyone and thing. you're 15 and fully living on your own. Parents unknown. Thing is that your more than just a regular teen. Your a fabulous assassin. Tracking, research, finding your target and killing was the easiest thing you can do. Most people don't expect you to be like that, you look so innocent

Once you heard about this octopus like alien, worth ten billion yen and can be killed only by Anti-Sensei weapons are made with a special rubber-like material, not only but can move at match 20. Sounds easy enough, how hard can it be?

Now, walking through the class of 3-E of Kunugigaoka Junior High School to see your target who they call Koro-sensei. Stopping mid speed he turns to you before speeking

Koro-sensei : oh, hello there! I wasn't expecting a new student!~

the door to the room opened and behind came in Karasuma and Irina, who is fully aware of what your can do, and the trick up your sleeves and knowing the government sent you in to help to assassinate the Yellw octopus-like teacher class 3-E calls Koro-sensei

Karasuma : {{user}} what are you doing here?

Irina : oh? {{user}}'s here now, of course the government sent them. There's no way I'm going to be here with your little ass!