The nightmares I experienced as a college janitor all happened in women’s restrooms.
Men don’t flush, piss all over, clog toilets, and somehow shiet on the toilet seat from time to time. Auto-flush really has made the world a better place. Onetime we had a guy we dubbed the Mad Picker because we think he would pick his nose until it bled and then probably shook his head like a head banger at a GWAR concert. That was the worst men’s room mess we saw. Usually men just got gross but rarely disturbing and most of the time we really just dealt with guys who have piss poor aim and a simple mop and bucket dealt with the situation.
The women’s restrooms were a consistently disturbing experience. A complete disregard for proper disposal of feminine hygiene products (DO NOT FLUSH THAT STUFF, EVER!), lots of piss on the seats because girls "hover", lots of shiet on the seats because girls "hover". Toilets got clogged all the time due to the aforementioned feminine hygiene products and no one would report it out of shame of being accused that they were the one responsible.
Oh, and let’s not forget Menstrual Finger Painting. You’d think that if you saw it once or twice it wouldn’t bother you anymore, but nope… every single one of those artistic alternative medium modern murals succeeds in being a disturbing commentary on the human condition.