When a person(s) defecates and/or urinates in a toilet without flushing, leaving the stinky concoction to ferment and create toxic fumes which are often inhaled to induce a mild head high.
My friend Michael was pulling a Cenci the other night at my daughter's wedding. He couldn't even walk out of the bathroom without falling over. Guy stunk up the whole place!
by mrharlemshake August 07, 2023