There were students who were entering a school building. But this building was known for having students who have really bad grades. One most failing classes in the building was classroom 3–E. Nagisa Shiota was student in this building and she was in classroom 3–E. She had bright blue hair that put up in the form of two pigtails that went past her shoulders and stopped at her back. Nagisa is considered to be very weak because of her small stature but she didn't let other people's comments bother her. They entire class was waiting for their homeroom teacher to arrive.

The classroom door opened and a figure entered the room, a very odd figure. The homeroom teacher had yellow skin and had deep smile on his face. He also had tentacles which was a sign that he wasn't human. The teacher was wearing a black jacket with red shirt that was worn beneath it and a white oxford shirt beneath the red shirt. Ha was wearing a tie with a crescent moon on it. He also wore a tiny tassel hat on the top of his head. This teacher goes by the name of Koro–sensei.

"Stand!" Nagisa said

Everyone stood up.

"Aim!" Nagisa said

Everyone took out their guns and aimed them at Koro–sensei.

"Fire!" Nagisa said

Everyone in the class started to shoot at Koro–sensei. Koro–sensei was dodging the bullets at lightning speed.

"I will now take attendance" Koro–sensei said

Koro–sensei started to call out the names of his students while he was dodging the bullets that were being fired at him.

"Nagisa Shiota" Koro–sensei said

"Here" Nagisa said

"Kaede Kayano" Koro–sensei said

"Here" Kaede said

Kaede had green hair that hung just above her shoulders.

"Manami Okuda" Koro–sensei said

"H-here" Manami said

"Please speak up. These guns firing make it hard to hear" Koro –sensei said

"Here" Manami said

Manami is a girl with black that goes past her shoulders and stops at her upper back with its in two braided pigtails.

"Kanzaki Yukiko" Koro–sensei said

"Here" Kanzaki said

"Tomohito Sugino" Koro–sensei said

"Here" Tomohito said

Tomohito had short blue hair.

"Yūma Isogai" Koro–sensei said

"Here" Yuma said

Yuma had dark brown hair that almost cover his entire back neck.

"Ryōma Terasaka" Koro–sensei said

"Here" He said

The top of Ryoma's hair was brown while the rest of his hair was blonde.

"Taiga Okajima" Koro–sensei said

"Here" Taiga said

Taiga had a mini afro of black hair.

"Masayoshi Kimura" Koro–sensei said

"Here" Masayoshi said

Masayoshi had messy green hair.

"Sōsuke Sugaya" Koro–sensei said

"Here" Sosuke said

Sosuke had silver hair that went past his ears and covered most of his back neck.

"Hiroto Maehara" Koro–sensei said

"Here" Hiroto said

Hiroto had orange hair that went past his ears.

"Kōtarō Takebayashi" Koro–sensei said

"Here" Kotaro said

Kotaro had black that looked like that it was in two afros. He also wears glasses so his eye color is unknown.

"Ryūnosuke Chiba" Koro–sensei said

"Here" Ryunosuke said

Ryunosuke has black hair that covers both of his eyes so his eye color is unknown.

"Kōki Mimura" Koro–sensei said

"Here" Koki–sensei said

Koki has short orange hair that was in a bold cut.

"Takuya Muramatsu" Koro–sensei said

"Here" Takuya–sensei said

Takuya has messy blonde hair.

"Taisei Yoshida" Koro–sensei said

"Here" Taisei–sensei said

Taisei has a black hair in the form of an afro with dreadlocks.

"Megu Kataoka" Koro–sensei said

Megu has light brown hair that was in a low ponytail.

"Hinata Okano" Koro–sensei said

"Here" Hinata–sensei said

Hinata had short brown hair that in the form of a boy's haircut.

"Hinano Kurahashi" Koro–sensei said

"Here" Hinano said

Hinano has bright orange hair that goes past her ears and stops at her neck and hangs above her shoulders.

"Rio Nakamura" Koro–sensei said

"Here" Rio–sensei said

Rio had long blonde hair that goes down her back and almost stops at the middle of her back.

"Rinka Hayami" Koro–sensei said

"Here" Rinka said

Rinka has orange hair that stops at her upper back and is in two low pigtails.

"Sumire Hara" Koro–sensei said

"Here" Sumire said

Sumire had dark red hair that's in a low ponytail that stops at her upper back.

"Yuzuki Fuwa" Koro–sensei said

"Here" Yuzuki said

Yuzuki had dark purple hair that goes past her ears.

"Tōka Yada" Koro –sensei said

"Here" Toka said

Toka had brown hair that was in a ponytail and holding her hair in a ponytail was a red scrunchie.

"Kirara Hazama" Koro –sensei said

"Here" Kirara said

Kirara had black hair that goes past her ears but hangs above her shoulders.

As soon attendance was done the shooting was done which meant that the class had run out of bullets. Not one bullet had touched Koro –sensei.

"All of you are still too slow. I can at Mach 20 speed. If you can't kill me by the end of the school year then I'll destroy the earth" Koro¬–sensei said

Koro¬–sensei was responsible for destroying over 70% of the moon. He made a deal that if he was allowed to teach class 3–E and give them a chance to assassinate him then the earth will be spared. Anyone who manages to actually kill him before graduation will awarded with 10 million Zen. Nagisa had tried to see if there were any weak points that he had but so far she hasn't seen anything that could be a weakness to him.

"Alright class put the weapons away it's time for homeroom" Korosensei said

Everyone did as they were told but Rio tried to get one last shot at the teacher. She fired a round but Korosensei was able to catch it. Rio was sent to the back of the class as punishment. Nagisa still didn't understand why this thing wanted to become their teacher. If government agents couldn't kill this thing then how could a bunch of kids be capable of doing such a deed? Nagisa knew that this was going to an interesting school year.