Welcome to Demon-School, Iruma-kun

Iruma and the others continue to prepare for the Battler Party. The launchpad for the fireworks is almost complete, so Iruma goes to look for Kiriwo. Suddenly, Iruma’s ring starts dragging him and is led all over Babyls until he finds a mysterious hidden room. Kiriwo was behind those doors planning a certain project. We also find out exactly who Kiriwo had been talking to on the phone. What does Iruma find in the mysterious room?