Earp slop, bring the mop slang
The idiom means someone has vomited.
To be more specific, earp is a sound used to express your feelings when you see something awful or disgusting. (similar to some sounds like eww, oops, wow, omg, …). Slop means liquid or wet food waste and the mop, a stick with soft material attached to one end, is used for washing floors.
Earp slop, bring the mop. Somebody was sick.
See, what’s in the kitchen? Earp slop, bring the mop.
To vomit
1. To laugh with shyness and embarrassment
2. Used to say that someone vomits on the floor, whether it's carpeted or not
To spew or vomit
Used to say that someone vomits into the toilet, usually as the result of drinking too much alcohol