if a dude sleeps with a girl and doesn't shower, gets up the next morning and can still smell her on his member... she made his dick stink... thus a "cockskunk"
"Dude, I swear I could still smell that cockskunk this morning when I took a piss...."
a male who is very good with the ladies, a womaniser, some one who is seen as a 'man slag'. Even though he is seen as this he is able to 'pull' girls. Usually are very good at fornicating.
'hey bekki, did you hear about tom hes a real cocksy, i really want to get with him, hes meant to be amazing in bed'