The fact that the Leanne in the game had met and had been attacked a couple of times by an "unidentifiable" person, then it only shows her in bandages is a little suspicious. Although it is sort of unnecessary and troublesome to draw out scenes of that, it could also indicate that when she met the murderer she was alone. So she might have injured herself or something to create the illusion that there is a murderer. So when she murders Cecillia, people will just conclude it was the murderer.
Also since we can conclude from the later chapters, that the Leanne right now is her fujoshi friend, that is why there was no article about a killer. Her friend probably wants to see the BL scenes, which is why Cecil probably felt watched when she was with guys. I think that also explains why the "murderer" didn't kill anyone.
