The whole first volume is normal band stuff, playing at games stuff like that, right? But in the epilogue of volume 1, the band receives this HUGE box of VR headsets. Turns out these headsets were enchanted by an entity unknown, that's when the main character becomes known as Simon. He came in late, and almost everyone else who came on time went evil in the universe the headsets places them into. Simon wears the headset and, since he puts it on later, the full code doesn't have enough time to load. Simon, as well as one other, is not turned evil. They meet allies in this new universe and work with them until the final boss; the Entity. The sub bosses are the band directors who also wore the headset. The other evils are pretty much like Minecraft mobs such as zombies.