The one who seduced you, screwed you over, broke your heart in a million pieces, and laughed about it.

SUPERNATURAL

The old flame you don't see very often any more but whom you still really enjoy getting together with for a few drinks and maybe a pleasant nostalgic romp:

SUPERNATURAL S1-4

The mysterious dark one whom you used to sit up with talking until 3 AM at weird coffee houses and with whom you were quite smitten until you realized s/he really was fucking crazy:

SUPERNATURAL

The one you spent a whole weekend in bed with and who drank up all your liquor and whom you'd still really like to get with again, although you're relieved s/he doesn't actually live in town:

SUPERNATURAL

The steady:

SUPERNATURAL

The alluring stranger whom you've flirted with at parties but have never gotten really serious with:

SUPERNATURAL (if by not serious you mean TOTALLY SERIOUS)

The one you hang out with and have vague fantasies about maybe having a thing with, but ultimately you're just good buddies:

SUPERNATURAL S1

The one your friends keep introducing you to and who seems like a hell of a cool person except it's never really gone anywhere:

SUPERNATURAL (BUT IT WENT ALL THE PLACES)

The one who's slept with all your friends, and you keep looking at them and thinking, "How the hell did they land all these cool people?"

SUPERNATURAL

The one who gave you the best damned summer of your life and against whom you measure all other potential partners:

SUPERNATURAL (it was a spring, not a summer, but same idea)

The one you recently met at a party and would like to get to know better:

SUPERNATURAL (S7)

The old flame that you wouldn't totally object to hooking up with again for a one night romp if only they'd clean up a bit:

SUPERNATURAL (S1-2)

Your hot new flame:

SUPERNATURAL (S7)

The one who stole your significant other:

SUPERNATURAL