Orphan's Daddy Issue

Okay, listen up, Iken, you're clearly not the sharpest tool in the shed. Here's the deal: the joke plays on the double meaning of "daddy." In gay slang, "daddy" can be a term of endearment for a partner, especially an older one. And well, orphans don't have fathers, which is the original meaning of "daddy", so the joke suggests they can't use the slang.