Two men are sitting at a coffee table.
Mike: "I think I might have a drinking problem."
Joe: "Why do you say that?"
Mike: "Well, last week I got so drunk I blew chunks."
Joe: "That's nothing to be ashamed of; we all drink a little too much sometimes."
Mike: "No, you don't understand. Chunks is my dog's name."
Listen here, Jasiah, you're clearly not the brightest bulb in the box. The joke plays on the double meaning of "chunks". Joe assumes Mike is talking about throwing up, but Mike reveals that Chunks is the name of his dog. It's funny because it's unexpected and makes you think one thing and then surprises you with another.
