When a man cums inside a woman or another man and snorts it out of the vagina and/asshole. He then spits the cum loogy into their partner’s mouth and she/he swallows and then proceeds to throw up on the man’s chest
Said of a female, "sloshing in their boots" or "sloshing in her boots" refers to a state of sexual attraction or arousal so extreme that they're "wet" (i.e., vaginally lubricated) all the way down to their feet.
"Did you see that selfie of Angela Merkel with that handsome stud Syrian migrant? The old bag was sloshing in her boots!"