A poopcheek is a complete idiot, A person who does stupid & has an extreme lack of common sense. Always acts like they are either wasted or stoned when they are completely sober. Clumsy & has ridiculous behavior. But one of the funnest people to hang out with.
Guy 1: What was she on last night?
Guy 2: None, she always acts like a dumbass.
Guy 1: Oh, whatta poopcheek.
Guy 1: Yeah but she's fun as hell!
Girl 1: Oh my god, I just fell all the way down the fuckin' stairs.
Girl 2: WHAT THE HELL IS WRONG WITH YOU?!
Girl 3: She's such a poopcheek!
When you don't want to go back to work/whatever else you're doing, and proceed to stay on the toilet far too long looking at Facebook posts, Instagram pictures, news articles, playing 2048, etc. - often far longer than it has taken you to actually poop.
This may also be due to fear of wiping in some individuals.
Poopcrastinating in its various forms:
1) I had a bunch of TPS reports I didn't want to do, so I poopcrastinated on the toilet for a solid 20 minutes and got a new high score on candy crush.
2) I had a huge essay to write after I finished my Econ homework, but nature called and I proceeded to poopcrastinate for a half hour on instagram.
3) Person 1: "Where is Bob? He went to the bathroom a half an hour ago." Person 2: "He's probably poopcrastinating."