Mark Sheppard as Crowley
Mark Sheppard as CrowleyFacebook/ Supernatural

Mark Sheppard, who plays the charismatically sinister demon Crowley in The CW show "Supernatural", turns 51 on Friday, 30 May.

Although he has played investigator James Sterling on "Leverage" and lawyer Romo Lampkin on "Battlestar Galactica", Crowley is Sheppard's most popular role. As Crowley, he gets to say some of the most blatantly cruel and hilariously sinister dialogues.

As fans awair "Supernatural" season 11, here are some of the best quotes of Crowley, The King of Hell, from all the seasons so far:

Two Minutes to Midnight (Season 5 Episode 21)

Dean: You sold your soul?
Crowley: Oh, more like pawned it. I fully intend to give it back.
Dean: Well, then give it back!
Crowley: I will.
Dean: Now!
Sam: Did you kiss him?
Dean: Sam.
Sam: I was just wondering.
Bobby: [innocently] No!
[Crowley shows a picture of his cellphone of them kissing]
Bobby: Why'd you take a picture?
Crowley: Why do you have to use tongue?

The Man Who Would be King (Season 6 Episode 20)

Castiel: Don't worry about the Winchesters.
Crowley: Don't worry about... what, like Lucifer didn't worry? Or Michael, or Lilith, or Alistair, or Azazel didn't worry? Am I the only game piece on the board who doesn't underestimate those denim-wrapped nightmares?

Survival of the Fittest (Season 7 Episode 23)

Crowley: Now, what do you have to say for yourself?
Castiel: Well, I'm still honing my communication strategy. I-I haven't even been back to Heaven. I keep thinking there are no insects up there, but here we have trillions. You know, they're making honey and silk and... miracles, really.
Crowley: What are you talking about?
Castiel: Um, preferring insects to angels, I guess. Here. I can offer a token, if you like. It's honey. I-I collected it myself.
Crowley: You're off your rocker. He's off his rocker! Is that it? Heh, karma's a bitch isn't it?
Dean: Look, did you come here to donkey punch your old grudges, or to help us get Dick? Pick a battle!
Crowley: Well, I'm vexed. I'd *like* to do both! But where's the fun in clobbering a ball of wet fur? Text me when Sparkles here retrieves his marbles, I suppose.

Sacrifice (Season 8 Episdoe 23)

[Sam injects Crowley with blood] Crowley: Aah! Aah! "Band of Brothers"? "The Pacific"? None of this means anything to you? All those motels, you never once watched HBO? Not once? "Girls"!
[Sam looks back at Crowley quizzically]
Crowley: You're my Marnie, Moose. A-and Hannah, she just- she *needs* to be loved. She deserves it. Don't we all? You, me? We deserve to be loved. [shouting emotionally] I deserve to be loved!
[softly, almost whispering] I just want to be loved.

Do You Believe in Miracles (Season 9 Episode 23)

Dean: How's Hell, Crowley?
Crowley: Hell's fine. Hell's like a Swiss watch. Don't worry about Hell. Hell's complicated.
Dean: "Game of Thrones" is complicated. The shower sex - that's complicated. Hell ain't complicated. Your problem ain't Hell. It's you.
Crowley: Fair enough. What's your problem, then?

The Prisoner (Season 10 Episode 22)

Crowley: You're right. I am a monster. And I've done bad. I've done things you can't even imagine - horrible, evil, messy things. And I've loved... every... damn... minute. So, thank you, Sam, for reminding me who I really am.

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