1. a preternatural being, commonly believed to be a reanimated corpse that bites your dick instead of your neck.
2. a woman who unscrupulously exploits, ruins, or degrades the men she seduces.
3. a cocksucker
Jake: blah I vant to suck your dick! (lol)
Johnny: oh shit! Jake’s a penis vampire!!!
Duke: but there are no bite marks on his neck, how can this be happing?
Johnny: it was Emily, that bitch she bit his dick and turned him into a undead cocksucker.
A girl who will resort to promiscuous or flirtatious behaviour to get help, advice or anything else she wants from a helpless male victim. Once achieving her goals ("sucking him dry"), the penis vampire ignores the poor sod, treating him like a total stranger.
Male 1: Wow, I'm so bummed out, I thought I had a chance with Emma
Male 2: Why what happened?
Male 1: She asked me to help her study for philosophy and she was all flirty and I thought I was in but after the exam, she totally ignored me.
Male 2: That Penis Vampire sucked you dry!