Time Traveler at the Bar

Okay, listen up, you simpleton. You didn't get it, did you? It's funny because the barman makes a statement about not serving time travelers, and then, what do you know, one walks in right after. It's a bit like saying, "I never see any giraffes," and then, bam, a giraffe shows up. It's all about the unexpected timing and the absurdity of the situation, you troglodyte.