One day, class 3-E of Kunugigaoka Magic School receives a special mission: to kill their homeroom teacher, the Demon King Koro-sensei. To improve their odds of success, the class seeks out the three most powerful warriors—Karma Akabane, Itona Horibe, and Ritsu—who subsequently join their ranks. Even with their assistance, completing the mission proves to be an insurmountable task, as they are not the only ones hunting the Demon King. Koro-sensei Quest! depicts the comedic adventures of Nagisa Shiota and class 3-E as chibi magical students. Trained by none other than their very target, the students face challenging yet hilarious situations throughout the perilous mission to defeat the Demon King.