Second for gross, smelly, stingy, savoury condiments.
Echoing what ive put on previous posts, there was a session where the other (really nice, lovely, kind) guy really REALLY wanted to give me a 'nasty' gunging. I went for it...and yeah, i hated it, but i could kinda enjoy it by proxy.
UNTIL a catering size vat of something i absolutely CANNOT stand (bad experience in infancy i think, as it is borderline phobia for me, i just can't eat or be near this food) got dumped all over me. I didn't know it was coming. Gag reflex into overdrive, i was actually sick....not fun. Not his fault, but a WAM lesson learned!!!
Savory, with 2 exceptions: eggs are one of my favorites, and although I haven't tried it yet, I wouldn't rule out baked beans; really curious about the mixed consistency of a sauce containing a solid that's also sqishable.
I've tried most stuff. And a few of my worst are: soy sauce, vegetable sauce, used motor oil, industrial grease, food garbage from a dumpster, rotten fish from a restaurant.
I think out of all of those that I've tried the worst was the food garbage or the rotten fish. I smelled terrible for like a week after both of those.
Not so much a substance, but the one thing that is guaranteed to make me utterly hate a scene is anything to do with toilets. Toilets are for piss and poop, the idea of any kind of WAM involving a toilet makes me want to throw up. A bathroom where there is a loo, even visible in the edge of the shot, but the WAM takes place in the bath or shower, fine. But anything where the WAM actually involves the toilet? Take off and nuke the entire site from orbit, it's the only way to be sure.