Supernatural's Dean and Crowley have gone from mortal enemies to tentative drinking buddies, and the duos unnatural relationship will prompt a much deeper problem as season 10 moves forward.

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Crowley and Dean have upped their friendship to "Jerk, B-tch" status, but a human Dean and the King of Hell may continue their collaboration in the future.

"You're going to see this relationship between Dean and Crowley really be put to the test," said executive producer Jeremy Carver, according to Entertainment Weekly. "Look, this is sort of a surprising relationship between the two guys that formed last year and I think both are a little bit surprised by the fact that they actually, in a weird, begrudging way, sort of feed off each other even when Dean isn't a demon."

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Like the Winchester's friendship with Castiel, their begrudging alliance with Meg, and Sam's dalliance with Ruby, a partnership with the King of Hell isn't seen as particularly normal.

"And at a certain point here in this season, this idea of humans being friends with demons being friends with angels, it's all going to come to a head of 'Who are you? Who am I? And am I really the type of person who is friends with this type of person or monster?'" Carver explained to Entertainment Weekly. "And it's all going to come to a head."

Find out more when Supernatural airs Tuesdays at 9 p.m. ET on The CW. Click the video below to see a preview of the series' next episode, "Reichenbach."

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