Euphemism used by gay men, to describe the ejaculate, or sperm that is generated by the male.
Originally used in reference, in a humorous connotation, to the sperm generated by homosexual males, that a wealthy woman has in attendance to her.
Can also refer to the coating on a penis, when removed from an ass, when no condom is used. This is created by the natural lubricants within the anus, that can make the penis appear to have a coating.
In that definition, usually refers to a male having anal sex with a female.