Tonya: Sure, give me a sec to dismount. That lube we used will make it extra-sticky!
MAN: "Just a second, let me put my boxers back on, I don't want to leave slug trails all over your Egyptian cotton sheets."
Typically a slugtrail is created by a woman after pulling off her man after a good ride. The female typically rests her pudenda upon the man's belly, slides back and forth, and create a slugtrail.
Also used to refer to any wetness created after said ride on the sheets.
It can also be used as a gerund (slugtrailing). Typically used by skanky girls to refer to one anothers' feelings about an attractive male. See second example.
Yo, bitch stop slugtrailing after my man - ya stank ho!