If you listen closely...

Dresden Dolls (esp. Sex Changes, Half Jack, Backstabber, Necessary Evil)
Bright Eyes (esp. Lover I Don't Have To Love, The Calendar Hung Itself)
City and Colour (esp. Save Your Scissors)
Mass Undergoe (esp. The Flesh Parade, All The Knives In The World, Baby!)
Jack Off Jill (esp. Strawberry Gashes)
Evanescence (I don't know. I don't listen to Evanescence and never have.)
Jackalope

I am laughing so hard right now. Rad.
Join in with more suggestions?

Also -

Coheed and Cambria
Ladytron (esp. Destroy Everything You Touch, Runaways, He Took Her To A Movie)

You looking for stuff with a particular feel to the sound, or stuff with a particular feel to the lyrics?

In either case (and half as a joke) about about Amanda Palmer's Oasis?

"Possum Kingdom" by the Toadies is *totally* about a vampire, I've been saying it for years. . .

(okay, it's probably *really* about teen sex, but given the context, I think either way is great here)

Oh, along the same lines as my previous suggestion, Amanda Palmer's "Astronaut" and "Runs in the Family."  But with here and the Dresden Dolls, maybe that's a bit too much Amanda, if such a thing is possible.

PS, who here has listened to Jack Off Jill?

Everyone who wants to know what Monsterhearts sounds like, go listen to Strawberry Gashes.

For some reason Jawbox's "Savory" is firmly lodged in my head while reading Monsterhearts threads.