Imaginary Lover
The person who is always sexually available and willing to indulge all of your fantasies when your real life partner will not. This person could be a pop icon, the hottie next door, an office co-worker or the one you masturbate to. Also the title of a cheesy Atlanta Rhythm Section song from 1978.
Last Friday Greg stared down at his Gin and Tonic alone at the bar, went home, and jacked off to his imaginary lover.