I think our two victims are KR and Yellow, with the killer being PI! Let me explain.:
So, it started with the race to the mansion. When Yellow cheated, PI got really angry at him for doing so, and also for hurting MF. The thing PI said under his breath was a murder threat, which just so happened to be a truthful threat to Yellow.
But what about KR?
What happened was that Obsidian secretly told PI about the incident, and he comforts her, and promises to pay them back.
So, PI went to kill them both.
PI first killed Yellow by absolutely cutting him open so much, which made the bathroom redder than the background of this scene.
KR then is next to go, with PI turning to her next, crushing KR's head in with a hammer he found earlier.
He then stared at his work, acting like he just found it, when everybody else came.
After yesterday's dilemma with White, he wanted to get revenge on someone who was part of it:Blue.
Let me explain how he did it.
White knew that Blue was a statue, and took advantage of that.
White first knocked Blue out cold with a wooden plank, and hid the plank in Blue's room.
He then dragged Blue to the kitchen and opened the oven, putting Blue on a tray and turning on the oven.
Blue woke up to him in the oven, and he tried to break out of it, but he died in the process.
However, blood from White's axe ended up on the kitchen counter, so there's a good clue.