I kind of wanted Cas to snap at dean saying “you wanna talk about cosmic consequences?? How about: the DARKNESS. And the fact that YOU KILLED DEATH, DEAN, I don’t think you get to say anything about what I did.”
So what's the general consensus then? Did they or didn't they have sex during the WW2? When I think about the amount of time they would've known each other during the war, I tend to lean more towards them having a very deep (but secret) relationship.