Flashback to the door of the Seoul Gateway, Jin busy opening doors and bowing at the various people passing through, including a pissed-off Sun walking out, passing by Jin as his upper torso is, once again, perfectly horizontal. And then he's accosted by a Symbol Of His Father The Poor Fisherman and Jin As A Young Boy together. Jin's Symbolic Father asks Jin if his son can use the bathroom, and the young man who reminds Jin of himself is accordingly hopping around bladder-burstingly while holding his crotch. Jin tells his Paternal Proxy that the hotel bathroom is for hotel guests only, and that there's a bathroom down the street. Then Jin asks the boy -- or Young Jin, because maybe time travel is possible -- if he can hold it, and the boy shakes his head, because when you are a boy you always know that you cannot possibly hold it, that you are moments away from unleashing a yellow tide on unsuspecting bystanders. Jin's Not Actual Father But For All Intents And Purposes Let's Call Him That pleads with Jin a little more, so Jin finally agrees, presumably worried that if this actually is himself as a young boy, doesn't want to damage the poor boy's plumbing, as that would have a Back to the Future-esque ripple effect and Present-Day Jin's kidneys would probably instantly explode. So he lets them in, telling them to be quick, but his boss is right there to lecture him about the people he's not supposed to let inside. Jin bows his head, apologizes. "Consider this your first warning," says Mr. Kim. Jin tries to plead his case that the little boy was actually him, and that if the kid should die of not being able to go to the bathroom, then Jin himself would have faded from existence, leaving the Seoul Gateway doorman-less, but Mr. Kim isn't interested: "He can piss in the gutter for all I care. You people are used to that." Would Mr. Kim really prefer that the boy had pissed outside the hotel? Kim tells Jin that if he wants to keep his job he should go find them and get them out of here. "Find" them? Psst, Jin: Try the bathroom.
But Jin, fortunately, has had enough, and he takes off his gloves and hat, to Mr. Kim's surprise, and stuffs them in his boss's hands. "Thank you for the opportunity, sir," he says, and walks off. He even quits jobs in disgust politely!