Destiel One-shots

Headcannon

You guys remember the episode where Dean gets transported to an alternate zombie-apocalypse like future, where Sam was possessed by Lucifer, and AU Dean ruled a place for survivors?

Well, I just got a sudden theory about that episode.

It never said WHY Sam said yes to Lucifer in the episode. But I've got an idea.

In the camp that AU Dean controls, Cas doesn't go out often. The only time we see him leave the camp is when it's the final standoff against Lucifer, and Dean brings along his most trusted people to die.

So, WHAT IF,

In this alternate world, Dean and Cas admitted that they loved each other and were a couple and everything, and Sam got jealous, because Dean would occasionally start to put Cas first, Sam second. 

So, to rebel, Sam said yes to Lucifer, sending the world into a downhill spiral. 

And when Dean takes over the group of survivors, he makes Cas stay inside the camp, fearing that since he no longer has his angelic powers, something bad will happen to him. Because Dean, no matter the universe, can't lose Cas. And in this particular AU, he's already lost Bobby, Sam, and everyone else that matters to him.

But the realization that his rejection of Michael and Sam's acceptance of Lucifer has caused the whole world to fall apart takes a toll on Dean, and he becomes the more cruel, more heartless person we see in the episode. This puts a strain on his relationship with Cas, and the two eventually break up, which is why Dean starts seeing other girls, resuming his womanizing, and why Cas falls into a drug induced fit of depression, popping pills and having orgies. 

This is also why AU Dean gets mad at his past self when Cas says "What? I like past you."

The seemingly innocent line could imply that Cas misses the way Dean used to be, and it brings him a bit of happiness and hope to see the old Dean he fell in love with once more. AU Dean, on the other hand, looks at his past self, and only sees the ignorance he had for turning Michael down, and for messing up everything he had with Cas and Sam.

But when it comes down to the showdown with Lucifer, Cas does come along with the group, because at the end of the day, no matter what has gone down between them- There's no one else Dean would rather have at his side then Cas. And Cas, being the intelligent, if socially awkward, person he is, may have even known what Dean was planning and went along with it anyway. Because, as it's been proven many times, Cas is entirely willing to die for Dean Winchester, no matter what tore them apart.

And, in a moment we don't see on screen, AU Dean tells his past self what really happened, explaining that it was Dean's favoritism for Cas that sent Sam over the edge. And that is why, when Dean returns to his own timeline, he never acts on his emotions for Cas, fearing that it will only lead to trouble.

But he never tells this to Cas, and so the two just spend seasons, back and forth, back and forth, never really admitting what they're feeling for one another. 

The closest Dean ever comes to breaking the promise he swore to himself is when he tells Cas that he needs him. He needs him, but he can't say that he loves him, for fear of what will happen because of it. 

Cas, being unaware of the situation, says I love you, but Dean doesn't say it back. This damages their private relationship, which is why there's more tension then usual between them from then on. But once Cas dies and is resurrected, Dean gives in, revealing his emotions to Cas, and things improve for the two, although they don't have time to worry about their relationship with everything going on.

And then, once everything seems to be calming, once Dean and Cas think they can really start to have a normal relationship- Dean becomes possessed by Michael, leaving Cas with the most heartbroken expression on his face, and rendering us full circle.

And this all same to me in a split second while watching a SPN themed song video. WTF BRAIN.