After surviving his first term at Babyls Academy, Iruma Suzuki’s life in the Netherworld only gets more complicated. The "Gluttonous Feeder Ring" has evolved, manifesting a wisecracking, sentient avatar named Ali who can physically alter Iruma's biology. This leads to the legendary "Evil Cycle" arc, where Iruma is transformed into the charismatic and assertive "Irumean." In this state, he leads the Misfit Class in a daring quest to claim the "Royal One"—the legendary classroom of the previous Demon King.

Beyond the classroom, Iruma must deal with a personality-switched Ameri, the flamboyant Ronove Lomeire’s attempts to take over the Student Council, and a school-wide field trip to the massive "Walter Park" theme park. However, the fun and games are cut short when a group of terrorist demons known as the Six Fingers orchestrates a massive prison break and monster attack, forcing the Misfit Class to prove their growth by defending the park and its citizens.