It is a normal day; everyone from deranged military girl Tanya Degurechaff and 16-year-old isekai protagonist Satou Kazuma to expansionist overlord Ainz Ooal Gown and demon sisters Rem and Ram go on with their daily lives. Suddenly, a conspicuous red button begging to be pressed appears before them. Overcome by curiosity, the otherworldly characters push the button, sending them to an unfamiliar world. With no way of escaping, the characters must lead a normal school life and make acquaintances with the others. One thing is certain: the classroom full of fan-favorite eccentric personalities never gets boring!

Despite completing all the tasks given to them, Ainz Ooal Gown, Tanya Degurechaff, Kazuma Satou, Subaru Natsuki, and the other members of Class 2 are surprised to find out that their role as students is far from over. With no means of returning home, the class of eccentric personalities is still mysteriously stuck in the unfamiliar world. Although, as they are becoming quite fond of each other, spending more time together does not sound that bad. With the unexpected arrival of new transfer students, the comedic antics of our beloved characters continue to grow. Thus, their bizarre yet nonchalant school life continues.