Мафия 2. The City of Lost Heaven

The clue is tricky. But it clearly points to only two people. I'm leaning towards the idea that the partially erased inscription says "vampires," meaning Zubr.
The fact that he noticed it himself is a trick aimed not at framing Stan, but rather at creating ambiguity so that no one gets framed. It's possible that they are both Mafia. Let's show some mercy – they probably won't show any to us at night.
Bitch, I was waiting for you at night, why didn't you come?
It's not a cheap trick, it's beautiful. But it's risky. Oh, how hard it was for me to wipe off the cloth and scales from myself... I even had to kill Stan just in case...