This Gentle Chaos, This Quiet Madness (слэш)

Sam has his soul back, but the brothers aren’t quite as home free as they’d hoped. Dean doesn’t realize that there’s still an outstanding contract on his own soul, meaning that unless they come up with a plan before the demons can figure out who gets to collect on it, he’s still bound for Hell and all his worst memories.
The answer comes in the form of an old adversary who can provide Dean with the protection he needs. All he has to do is offer everything he is to Gabriel’s alternate persona. To Loki.
But even when the ritual is complete and his soul firmly bound to a being he’s not even entirely sure he trusts, he’s still left fighting enemies on all sides. The armies of Heaven will stop at nothing to get to Castiel. The wall keeping Sam’s sanity intact is not as structurally sound as it should be. Demons are itching to come after Dean. And the archangel-turned-pagan-god at his side is annoyingly persistent in trying to win his affections.
Dean figures they’re all pretty much screwed.