suggestive fluid
An innocent liquid presented in sexually suggestive way.
A common example is when a character is covered in something that looks like cum (or, less commonly, pussy juice or urine), but is actually something innocent like ice cream, milk, mayonnaise, sweat, or lotion.
Don't tag actual cum as a suggestive fluid. Unknown fluids that look like cum should be treated as cum if there are no context clues to suggest otherwise.
Use ambiguous red liquid when the fluid looks like blood but you are unsure.