Sam and Dean scout on a few vampires in this clip from "Live Free Or Twi-hard." As the title suggests, this episode plays off the vampire craze in Hollywood.
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Dean is bitten and turned into a vampire on this episode. Seriously! Check out the official promo for "Live Free or Twi-hard."
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Supernatural Season 6 Episode 5 Quotes

Dean: Try uh, Lautner.
Sam: He's a werewolf. How do you even know who that is?
Dean: What are you kidding me? That kid is everywhere. It's a friggen nightmare.

Look at this. Watching her sleep, how is that not rape-y?

Dean