Hi guys. This is what i posted at another topic (This is the end) but it match with the question of "Who is the Guest":
I have been watching the drama video. I can understand Russian quite well but not so much that language they speak (it is another slavic language, i think it is Bulgarian or Macedonian). But some words are the same as Russian. From what i got, Suzan was mad because Hector got home quite drunk, with his brother. I don't know if the Hector's brother is actually the "guest" (he was watching the scene from the door at the start of the drama and ran way when things became ugly) - but i guess so, because she was screaming "had enough of your brother!" pointing at that door. She may had been a little to much closer to the boy, but now she was really mad about him (or just mad about Hector, using his brother as ammunition).
I couldn't understood the rest of the conversation because they started talking quiet fast and screaming in that peculiar language.