Unpleasant Bathroom Experience Ruins Potential Relationship

Third date. We had a picnic in the park by his apartment. All signs were positive: great conversation, shared interests, and good vibes. He invited me back to his to watch a movie, and before the movie started, I popped into his bathroom to freshen up. The bathroom was beyond gross for a single guy living alone. The toilet was black with mold, and the room smelled like pee. The shower had no curtain, and the tile had black streaks. There was shaving debris and tiny hairs all over the sink, and no soap to be found. I literally gagged. I faked a stomach ache and left. There was no fourth date. I'm still unsure how someone could live like that, especially since the rest of the apartment appeared tidy/clean.