Isekai Satsuriku Kagai Jugyou

The students of Class 2B, who were living ordinary lives, are suddenly transported to another world by an angel who changes their classes into characters from another world, such as heroes and wizards. There, the students are forced to participate in an "extracurricular activity" called an "Otherworldly Massacre Battle," where they must kill each other until only one remains. The students, who have become enemies in the other world, each use their sword and magical abilities to engage in a life-or-death battle filled with friendship, betrayal, and despair.

(Source: Shinchosha, translated)