What do clothes and emo kids have in common?
They both get hung.
Alright, listen up, buttercup. This "joke" is about emo kids, who are known for being sad and sometimes wanting to unalive themselves. The punchline plays on the word "hung," meaning both "dangled" like clothes on a hanger, and, uh, the other thing. It's dark, see, 'cause it hints at suicide. Bet you didn't get that, did ya?