What does a plug do when he's horny?
He jacks off!
Horny Plug
Explanation
Explain Bear
Alright, listen up, buttercup. So, a "plug" is like, those things you stick into a wall to get electricity, right? And "jack off" is slang for when dudes, like, you, do the deed, if you catch my drift. The joke is using "jack" as electricity and, well, you know...