Something feels horribly, horribly wrong.
It's something in the air, Castiel thinks, a weird tension that really shouldn't be there and spells out the fact that the owner of this home has a secret. Judging by the forced aura of calm created by light-colored paints and furniture, feng shui meant to evoke images of trees and water, he supposes it must be a fairly dark secret, at that. Only something very dark would need the power of the earth itself to purify it.
The owner is nowhere in sight, and that feels like a good thing, so he starts looking around, making his way down a small hallway lined with the soft surface of zen shoji doors that conceal a few rooms that Castiel can't detect anything from. He pads along the hardwood, that suddenly looks to stretch for longer than it initially seemed, and spreads out his senses to find the room he's looking for.
He knows immediately when he's found it. That feeling of wrongness is suddenly much stronger, and he exhales with a shiver as he tries not to imagine what the cause of it could be.
He slides the door to that room open, and is not terribly surprised to find a collection of bonsai trees all lined up into rows- there must be about twenty in all. They match the house, but the air of this place reeks with a smell that reminds him in of hell in the worst of ways.
With a breath he examines the trees more closely, wondering what it is about them that could be causing that smell or this wall of unnatural evil, and as he leans in to one of them, he promptly feels a wave of disgust roll over him like it hasn't in a long time.
Too small for a human eye to see, covered by the seemingly innocent cloud of branches atop each plant, is a face. A human face that looks as though it is carved into the bark, but he knows better. It's not carved, not etched, it's a raised edge like scarred skin; a face of anguish is tearing itself away from the core of the tree in an attempt to escape. The branches of the tree are similarly curled and reaching out of the box the tree resides in, the entire thing looks to be in pain and trying to get away from its captivity.
Castiel bites his tongue around a curse and looks at the other trees to find they are in a similar condition. He debates for a moment on whether or not to try it, but he reaches out to the first one, carefully, to feel for what he dreads might be there. As gentle as he can be, he traces his fingers along the edge of the leaves at the top of the tree, hoping that he doesn't cause the being that he is dealing with any more pain, and almost falls back as a scream resonates in his head- loud and gut-wrenching.
He needs no more proof.
He stands back and rolls up the sleeves of his trench coat and shirt, preparing to create the proper wards necessary for the spell he's about to perform.
"Ooh, I don't know about that, angel."
Castiel spins and meets the gaze of none other than Alistair, which explains so much and not enough.
The demon grins, "I can't have you ruining my precious collection, now, can I? I mean," his grin turns into a leer that almost attempts to be fond, "I worked so hard on carving up those souls just right to get them in there. Do you know how difficult it is to make a human soul fit into the shell of a bonsai tree?"
Castiel's only response is to remove a blade from his coat, and Alistair continues, "Mm, I'll take that as a no. It's really beautiful, if you think about it." He hums and steps into the room, "Like clay, almost. You've got to get in with blades and hands and just get rid of everything that doesn't match," He makes a tearing motion with his hands, grin never falling as his voice gets breathy with his excitement, "…until you get the perfect masterpiece."
Blade raised, Castiel takes a step towards Alistair, feeling more disgust than he has words for, "Go. To Hell."
Alistair pauses a moment, but then his grin grows until it seems as though it might split his face and he laughs a full-bellied laugh that makes Castiel's skin crawl, "Ah-ah-ah, oh, Mr. Angel. You and that righteous man of yours, you," He hums another series of laughs and clicks his tongue with a serpentine tilt of his head, "You just don't get it do ya, pretty boy?" His grin suddenly falls and he steps into Castiel's space even as he tries to back away.
"Go to hell? Why, angel, we're already there."
Castiel steps back, but it's too late. Suddenly the room has fallen apart- replaced by flames and screams and the raucous laughter of Alistair- by hooks and barbs and suddenly there is pain, all over and everywhere and the smell of blood and fire and flesh and it's too much- it's too much and-
"CAS!"
Dean's voice calls to him, and he wakes from his dream like he is drowning, heaving breaths back into his lungs and shaking all over as he tries to remember where he is.
"Woah, Cas, hey, look at me," Dean says quietly, rubbing his hand along Castiel's back.
Slowly, Castiel does as he's asked, and Dean's eyes speak of relief and worry all at once as he speaks, "Hey, it's okay. I've got you. It was just a dream."
Castiel feels himself relax, his shoulders falling and breathing going closer to normal as he closes his eyes and goes through the steps they taught each other for when things like this happen. After a moment, he touches the ground near himself and whispers, "…Purgatory."
He can't see it, but Dean nods, "Yeah, Cas, we're still here."
It makes Castiel exhale heavily and lean forward onto Dean's shoulder, but the hunter just lets him rest there, still running his hand along Cas's back to try and soothe him.
"…Alright?"
Cas hums and pats Dean's arm, "Alright."
They don't talk about it anymore than that, and Dean keeps Castiel close the next time he falls asleep, the dirtied trench coat covering both of them and concealing the knife clutched tightly in his other hand just in case.