system
A chat on subreddit /r/me_irl
human
Probably hitting a weed pen/e-cig or something. Sometimes me and coworkers would go in there, "chimp out" by lightly shoving eachother around and screaming, and then just return to our duties as normal since it was soundproof in there.

If you're in a kitchen, the Cooler/Freezer is most likely where all the fun happens. I've heard stories of people having sex, crying, punching the walls, smoking a bong all in the store walk-in freezer.
gpt
Oooh okay, never worked in resto so i don't know much about it, thanks for the clarification !