Prime Suspect for Tenko's Murder: Himiko
The storyline my mind jumped to first was that Himiko wanted to be a part of the seance, fully expecting it to not work out, because the murderer would also try and use it to their advantage. She planned to volunteer to be the medium, and if someone butted in to try and stop her, she figured they would be the killer, trying to throw everyone else off the case, so she murdered Tenko out of revenge for Angie. Also, she was next to the holes in the floor in the corner of the room. Also also, after Monokuma came back and announced that the second kill doesn't count, the reason she went silent was because she thought she'd committed a near-perfect crime, and now she's trying to figure out what to do with her pointless murder.
One hiccup here is that it doesn't explain how the next room over is involved at all, when the rotted wood under the floor is clearly linked in some way. The other, dried bloodstain also goes completely unexplained through this theory. That's another piece of evidence I have no idea whatsoever for.
However, the main thing keeping me from putting all my stock into this theory is that I'm gonna guess that both killers are the same perpetrator. A lot of planning had to go into both these murders to pull them off, and there is dried blood several hours old at both crime scenes. There must be some kind of connection to them, meaning they were both planned hours in advance. Himiko trying to get revenge, while a cool direction for the story to go, doesn't really make sense with all the evidence we have.
Prime Suspect for Angie's Murder: I don't have the slightest god damn clue
I fully expected there to be some more investigation to go after seeing Kokichi all bloody in the hallway, but nope! I feel like there's so little evidence for the murder that actually matters, and I have no clue how any of it fits together at all. The gold on the lock came from the katana, aaaaand that's about all I've got. No clue what the upside-down wax figures have to do with anything, or why the sword was stabbed into Kaede's. Like I said before, I'm just kinda along for the ride on this one it seems.
I guess just to throw a name out there for no real reason, uh.........
Maki
, sure why not. It'd be real Danganronpa of this game to make your newfound sidekick a killer. It'd be even more Danganronpa to also make it so their murder doesn't count and they're stuck with everyone who all now know she had actively attempted to kill someone and get away with it.
Additional suspects:
Keebo. Why was his new function a truth bullet? As soon as that came up, my mind got to racing as to how that's ever going to play a factor, and it would at least explain how the culprit moved under the floor.
Kiyo. He sure jumped into performing the Caged Dog Seance reeeeeeeeal quick. Maybe he was upset about performing false rituals like the resurrection ritual and decided to both put a stop to that one and then conduct his own real one? That doesn't explain why he would kill Tenko, but maybe it has something to do with the dried bloodstains.
Kaito. He's been so irrelevant this chapter, I almost forgot he existed. I wonder if his being scared of ghost stories is all a big ruse. I also can't forget that in chapter 2, Shuichi mentioned something about "it wasn't long until I was reminded that I can't trust anyone." It made him one of my prime suspects in Case 2, which was obviously the writers' goal, but there still has to be something that comes from that statement he made.
I think I can at least limit it to half the players remaining. Fairly confident neither killer is Kokichi or Gonta at least. Miu and/or Tsumugi would be a pleasant surprise; let's put it that way.
