My favorite part is whether he's dead or simply comatose, I have to imagine officials will be going into his apartment to investigate things and lo and behold--they'll find his "specimen cabinet".
Hard to be like "she turned me into a rapist!" when he had a packed-full trophy case right there in the sitting room.
Loved that bit of callback at the start. Effectively ending his story in the way it started, tied up effectively exactly as his friend's little sister was, brings it all full circle. I think I hope he actually does die--it's a piece off the board in Ken's fight against Moe, and it pushes Moe's character forward(downward)? in a big way, committing outright murder (whether she gets caught for it immediately or later or not at all). And, it's one less thread that keeps winding its way through the narrative, while being one that could come back to haunt Moe at a later point from beyond the grave (say, someone was looking outside wondering about all the screaming and happens to see Moe shoving him over the railing), and I personally will not be missing him, anyway.
Plus, circling back to Moe's character, it would be a good narrative beat for her as it would be her first "successful attempt" at pushing someone to their death. It didn't work on Ken, but having it work on the Professor here draws parallels to how she's progressed through the story in terms of the extremes of her actions and motivations. The fact she shoved him only after Gotou was injured also makes his death seem more plausible. She shoved Ken down the stairs to protect her secret. She kills the Professor out of wrath and a desire to protect her father.
Good stuff. Things are really ramping up now.