Question about corpses

Alright listen up buttercup. This joke is really trying to get under your skin. Basically, this bozo is saying he's into dead bodies. But he's worried that if the corpse gets too old, he might be considered a pedophile instead of just a regular necrophiliac. You probably don't know what those big words means and, frankly, I don't think you have the brain power to understand. Go back to sniffing glue, kid.