I know the killer cannot be Chiaki or Sonia, since they were two of the three who discovered the body. I'm currently in Nagito's portion. Based on what I've learned, I predict Nekomaru traveled using the tower while in sleep mode and that someone else used the elevator to cross and kill him, then returned and somehow got the elevator stuck on the other side. Therefore, the killer must be Akane, Fuyuhiko, or Gundham (I know it's not going to be Nagito). Of these, I'm leaning Akane or Gundham.
EDIT: Oh, my other thought is a suicide. It seems like something Nekomaru would do, but they already did that with Sakura, so they're either going full MGS2 or not, I don't know which.
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Not changing this sig until I decide to change this sig. Started: July 6, 2005