|The E Class and the Demon King|
|Romaji||Maō to E-gumi|
|Next Episode||The Red Devil|
|Japanese||December 23, 2016|
|English||January 11, 2017|
|Ending||Seishun Satsubatsuron Remix|
The E Class and the Demon King is the first episode of the Koro-Sensei Quest! anime. The episode first aired in December 23, 2016.
In the alternate universe set in RPG world, the students of Kunugigaoka Magical Academy are heroes under training and students of class 3-E are those with bugs - making them weaker than other heroes. They are tasked to defeat Koro-sensei, a demon lord who intentionally teaches them so they could defeat him one day.
The Demon King arrives in Class 3-E homeroom to start Class with their students and waits for his students to attack him.
The Class 3-E is later shown thatt they are very tired trying to attack the Demon King. Later the Demon King was mentioning how the students where battling in trying to assassinate the demon King with their bugs, magic and sticks and couldn't hit the Demon King once students begin complaining about how he's too fast and how they can't hit him one because of their level.
Isogai was shown with an armor with only the front side because he is poor he can't buy the fool armor. Later a flashback was shown of the Class 3-E of how they meet the Demon King and comander Karasuma Explain to the class how they have to kill the Demon King and of his incredible speed of '99999' *poking out of the window* . The Demon King made this desicion because the Class 3-E is know because of their bugs and weekness and decided to train them by killing him. The class 3.E was shown shocked complaining about their bugs. Yuzuki was asking Karasuma if they had a time limit, but it all depended of how they were doing. Later the Class decided to call kim "Korosensei".
The training began outside of the school tasking the Class to sacrifice the NPC slimes. The Class 3-E was shown running... from the slimes? Nagisa provoked a random bug where he because muscular and used fire magic that defeated the slimes. Later Nagisa didn't know how to stopped the bug and Korosensei freaked out, and were trying to solve it by going to a hot spring but didn't work.