It seems that Brain-kun was attacked in the hallway with a heated weapon that was scratched against the walls, which caused him to use the saxophone in anger. He was then chased into the lounge, where he used the saxophone in fear. He was assaulted with the heated weapon, subduing him enough that he could be hung. This killed him. The culprit then retrieved a sword that was used to remove his limbs, shedding only a minimal amount of blood. Three limbs were taken to the nearby bathroom, weapons room, and kitchen, while the right arm was taken to the weapons room.

There are two things I don't understand at all. Hermes falling asleep, and the actions taken with the several pieces of paper.