I have a few specific ideas in mind, and we can discuss them via private thread/ e-mail/ AIM, but here are the bare basics so I don't type up a wall of text:
1) A warlock or wereanimal (except werewolf) opposite a vampire. Based Anita Blake: Vampire Hunter. Themes would include power struggle/ politics. I will not be playing the vampire.
2) A warlock opposite a vampire. Original lore. Themes would include revenge/ body-stealing/ betrayal/ obsession. Again, I will not be playing the vampire, but the warlock would be just as old as the vampire, though not physically since he would be consciously jumping from one body to another.
3) A human opposite a vampire. Original lore again. Themes would include betrayal/ possibly unrequited love/ reincarnation (on the human's part)/ guilt (on both parts). No, I will not be playing the vampire.
4) A human opposite another human. This is a tricky line, and it would be just a bit supernatural - one character would have already died once but comes back the age he died without any of his previous memories up until he meets his former lover again. Themes would include suicide/ reincarnation (after a certain sense)/ a broken soul mate bond or unrequited love/ feelings vs. memories.