In the past I worked with severely mentally ill folks, and every so often you'd meet one who had a creative streak expressed with fecal "paints". I've also worked with folks with big, years-long drug addictions, and "explosive diarrhea out of nowhere" doesn't even begin to cover it.
Just walk away. In the "old" days we had to clean up stuff like that, but a decade or so ago they started requiring real hazmat response to anything that was wet - blood, excrement, vomit, indeterminate, etc. No one without medical quality gloves, face shield, and more should be interacting with anyone else's "stuff". Like I was taught in my last blood-born pathogens class: If it's wet and it's not yours, don't touch it.
Don't know about you, but I'm not going to start buying liquid milked from a cow, and stop buying liquid that was milked from a bunch of almonds, just because cow-milkers won't let almond-milkers say "milk". The non-dairy producers will just get creative and name their stuff something else, like Malk