A night on the streets/in a park, which can consist of snorting mephedrone, bonging salvia, chugging pints, eating dominos and chinese whilst blazing up a jay, and listening to dark tunes. Basically a night out with at least 3 people abusing their bodies for pure entertainment. It happens when there are no free houses available, the next best alternative.
"Mate my parents have decided not to go out, fancy a messy night instead?"

"Can't wait for this messy night to commence!"

"I've got blunts, ganja, maddy, budweiser, tarantula... this messy nights gonna be a gooden'"

"Alright i'll be there in a bit, this nights gonna get messy."
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