Dean watched his mom (his hunter mom!) pull away from the demon-controlled husk of her father’s corpse, the lip-lock unmistakable for the signing of a contract especially with the way she cradled John’s dead body in her arms. He thought he screamed in anguish, except only the weakest squeak popped out of his mouth, but loud enough for Mary to hear because she turned to look at him in the headlight beams. The half-defiant, half-terrified look on her face shook him because he knew that look; it was the same one he stared at in the mirror after he made the deal with the crossroads demon to bring Sammy back to life. There was no coming back from this, and Dean realized this was exactly what Castiel wanted him to witness. The inevitability of it all – Mary starting them all down this hellish road of demons, contracts, and death.

“You’re just like your mother,” John had wistfully said a few times during Dean’s childhood, a comparison he probably wasn’t meant to hear, but Dean had always preened because it let him know how he fit in the family. Even from a young age Sam was a carbon copy of John in looks and temperament, a fact that often made Dean feel like the odd man out especially during the turbulent teen years before Sammy took off for college. They knocked heads and fought like alpha dogs over the last bone because they were too similar to back down and it fell to Dean to make the peace.

Yes, John, I’m exactly like my mother – willing to damn everything for the man in my/her arms despite knowing better. Suddenly Dean, who’d built his entire life on the foundation of his parents’ perfect love, wondered if Mary really loved John as much as John thought, or if desperation for the deal she wrought and losing her parents made her cling to the “normal” she hadn’t really chosen so much as had the choice forced on her in the course of a few stunning hours. Her initial decision to run away with John was an emotional decision to leave the hunter world she didn’t want to be apart of, but would she have stayed with John if she’d had somewhere else to go? After all, she chose him because he was a civilian and the irony of it all made Dean want to vomit because he doubted his dad ever knew about the Campbell legacy.

“It’s time to go Dean,” Castiel quietly said, spooking the hunter who was watching his past superimpose itself on his parents’ past and realized that the way to Hell really was paved with good intentions. Campbell-Winchesters’ good intentions.

Between one snap and the next, Dean was no longer in the distant past but his present. He shook with a combination of adrenaline, pain, rage, and a despairing sadness that widened the tear in the space behind his heart, the crack begun with Sam’s desertion, and nearly consumed him when Sam died in his arms. Castiel, however, wasn’t finished with him because he still stood there looking at him with infinite patience.

“Dean, you must stop it.”

“Fuck you and the little dog you rode in on! What more do you want from me? I fucking tried, but Old Yellow Eyes escaped me.”

Castiel cocked his head a little, reminding Dean of the dog Sam adopted after he’d run off to Flagstaff when he was twelve. The thing was little more than skin and flea ridden bones, but he’d looked at Dean the same way when he’d broken into the trailer Sam was squatting in, as if questioning his presence in its world.

“You were never meant to stop Azazel, Dean. You couldn’t then.”

“So it was my fault,” Dean gasped, hands on his knees as he fought to keep the vomit locked behind his teeth. “I turned that bastard onto my family when I taunted him.”

“No.” The denial was implacable. “This is your destiny, to be Michael’s Sword, and for Sam to be Lucifer’s True Vessel. Azazel is just another tool in my Father’s plan for your family. If it was not him, it would have been another.”

Dean stood upright, eyes focused completely on the unassuming angel. “I will never say yes and neither will Sam!”

Despite Castiel’s human vessel, his face was always placid and serene as emotions never seemed to touch him, therefore the pity was unmistakable as he turned his blue eyes from him to the second bed. Dean followed and stared at his brother’s empty bed uncomprehendingly. He’d vaguely assumed Sam wasn’t awakened by their arrival and subsequent conversation due to some angel mojo, so he hadn’t thought to look.

“Sam started walking a dark path when you went to Hell and if he is not stopped, then it will just be a matter of time for Lucifer to rise using your brother.”

“I know my brother better than anyone alive and I’m telling you, there’s no way in Heaven or Hell that Sam would let that happen. This is the same kid who throws a fit if I’m rude to pushy old ladies.”

Castiel moved too fast for Dean to see because the next instant he was transported to another motel, more run down and seedier than the one he and Sam checked into, and he hauled around to punch the angel when a female voice moaned “Oh more, Sammy.”

Dean whipped around and saw a small naked female sitting on Sam’s lap holding her arm to his face even as her hips worked in a pattern Dean recognized. Sam pulled back, his mouth gleaming wetly in the barred lights streaming through the blinds at the window.

“I’ve told you not to call me Sammy. You don’t get to call me that.”

Dean couldn’t see the girl’s face since he stood at her back, but he could tell by the tensing of her shoulders and the muscles in back she was irritated by Sam’s response, though the saccharine sweet tone belied her body language.

“Sorry, sweetie, but you need more if you’re going to get stronger.”

Dean was irritated by the scene, mostly because he really didn’t need to see Sam’s hungry look as he gripped one small hip in his massive paw even as her arm pressed against his mouth, her body moving up and down as his brother increased his pace.

“Dude, I did not need to see Sammy getting some. They can’t sense us, right? I don’t need Sam thinking I’m spying on him during…this.” It was a miracle the kid had unclenched his asscheeks long enough to pick up a chick; then he remembered the girl he and Bobby found in Sam’s room when they tracked him down after Dean was resurrected. In fact, it looked like Sam had picked up a new fetish for tiny brunettes because this one was similar to that girl, actually. It was annoying to know that Sam hadn’t been around to worry about his brief disappearance into the past, but Dean couldn’t begrudge his brother getting his dick wet if it would help ease the strain Sam thought he hid so well.

“This is not a simple sexual transaction,” Castiel cautioned. “She is in a different vessel, so it is understandable why you do not recognize her.”

A sick feeling welled in Dean for the second – maybe third? – time that night. “Who is she?”

“Ruby.”

He ignored the wet sounds of sex and his brother’s nakedness to peer at the girl’s face. It was her, the girl they’d met a few weeks ago and Sam pretended was just some barfly he’d picked up for the night. This close it became apparent exactly what Sam was doing with her arm – his kid brother was gulping down demon-laced blood, eyes rolled back in orgasmic pleasure second to the one his body gave up a few seconds later.

“What the hell is he doing?”

The horror was thick in Dean’s voice.

“We do not know what Ruby’s plan is or who her master is, but whatever it is, it does not bode well for him or you. Sam is somehow obscured from our vision and we cannot understand what the point of it is, but know this: demon blood is addictive and Sam has been with her almost for the entire time you sojourned with the Fallen ones.”

Dean turned away when Sam slipped out of Ruby’s body, a flash of his slimy cock proving his brother hadn’t listened to any of Dean’s safe sex lectures over the years because he had fucked her bare. Ruby flopped to Sam’s side, a self-satisfied smile curling her lips even as her body relaxed into a boneless heap. Dean fisted his hands and wished he could smash them into the little hellcat’s face, pummel her until she was a bloody heap, and lock her in a Devil’s Trap until he could find a way to send her back to Hell permanently, or perhaps to the true death since she obviously escaped from wherever Lilith had stashed her the last time.

“Thanks, Big Boy,” she purred.

Sam snorted and heaved himself off the bed, grabbing his boxers and jeans lying crumpled at his feet and pulling them on in one swift motion. “You got what you wanted.”

“Like you didn’t get what you wanted either.”

The disgust on Sam’s face was somewhat comforting – no, no, it really wasn’t. Sam still had fucked a demon and drank her blood like it was Kool-Aid.

“I could barely smoke those three demons and their vessels died anyway despite being juiced. When are you going to step up my training?”

Dean couldn’t believe his ears at Sam’s question. This from the same kid who had to be drawn out of bed kicking and screaming for dawn training for most of his life, practically begging for more? Then he registered the first part of Sam’s retort.

“What does he mean, “smoke demons?””

Castiel stood stock still, his blue eyes wide. “No…no…”

Dean stepped closer to the angel and lightly slapped him to get him out of the loop he seemed to be in

“What, Cas. What?”

“It is only a myth among my garrison.”

He controlled his impatience with a deep breath and a slow exhale, though part of him was alarmed by the angel’s response. Castiel was the most unemotional being he’d ever met, so alarm and what he would almost call fright was not something he expected to see.

“What’s the myth?”

Castiel turned desperate eyes to Dean and a little tension seemed to leak out of him when Dean gripped his shoulder to keep his attention focused. “The longer a demon inhabits a body, it will completely take over, infecting the tissue, blood, and bones of the vessel until it reeks of evil. Over the centuries the demons have figured out how to spread the taint without necessarily taking over bodies; it is a twisted form of an angel’s Grace because the original Fallen Ones, who created demon kind, were once Angels themselves.

“Croatoan virus,” Dean breathed, his mind spinning back to the murderous Oregon town he and Sam barely survived.

“Yes.”

“But what does this have to do with whatever is freaking you out?”

“Sam was immune to the virus, in some part due to the blood Azazel forced upon him as a baby and his status as Lucifer’s true vessel. It means…” Castiel shifted and Dean could swear he felt the brush of feathers against his cheek. “…it means, his body can process demonically tainted blood and draw strength from it.”

“So you’re saying demon blood is the meth of the supernatural world?”

“This is not a time for levity, Dean.”

“Dude. Just tell me what the fuck this means and how I can stop it?”

Castiel breathed quietly for a moment, his blue eyes tracing Dean’s features, causing Dean to take a step back when he realized how close they were.

“You are him.”

“Who?”

The angel ignored the confused question and pressed on. “Dean, if Sam continues down this path he will become more than just Lucifier’s vessel. He will become a human demon.”

“Huh?” Dean knew he may not have Sam’s smarts, but he was far from stupid or slow on the uptake. “What’s that mean?”

“Do you know why my father banned angels from mating with human females?”

“Uh, something about their children being abominations.”

“Yes. The Nephilim had the powers of angel kind married to mortal flesh, in essence they could not age or die, but could procreate in a way angels cannot. When angels mate, they give up a part of their grace, dividing themselves until nothing is left. When Nephilim mated, they could create copies of themselves without losing any of their powers. This is why my father sent the flood to cover the earth; it was the only way to destroy the abominations.”

“And a human demon is an abomination in the same way?”

“He is a conduit of demonic power which is why Lucifer can wear his body without it wearing out even past the end of Sam’s natural years, though eventually the body would become so much dust and bones he would be forced to find a new vessel.”

Dean proved he had a facile intelligence when he immediately leapt to the correct conclusion. “But if Sam consumes enough of the twisted Grace inherent in demon blood, he won’t need Lucifer to use him as he’ll have the same powers as demons without needing to take over body after body. His own body won’t age or break down so conceivably he can live for hundreds of years.” Another thought struck him. “He was raised a hunter and those instincts would carry over so he could become Lucifer’s pet killer even if he didn’t say yes.”

“If he became demonic, he would think it a great honor to house Lucifer.”

He spun around and stared at Sam who was talking to a now dressed Ruby, indicating some time had passed since their blood session.

“This is why you can’t tell Dean.”

“I could make him understand!”

Ruby raised a dark brow. “The same Dean who went to the Pit and had a front row seat to the horrors of Hell. Yeah, sure he’d understand.”

“He doesn’t remember…” the pout on Sam’s face was the same one he’d had when he was still in diapers.

“Because of course Dean wouldn’t lie, even to spare his baby brother’s feelings.”

Dean had never hated anyone – Old Yellow Eyes included – as intensely as he did Ruby in that moment. Sam didn’t necessarily believe him about not remembering, but Winchester code stated you didn’t acknowledge weakness until the other person brought it up. The anguish welling in Sam’s changeable eyes proved how much he hated Dean’s pretense.

“See, baby, you stick with me a little longer and when you’re fully trained to kill the demons, you can show Dean exactly what you did while he was away.” Ruby’s faux sympathetic tone was grating, but seemed to reassure Sam, which enraged Dean because until now he was the only one who knew Sam well enough to ease him.

Castiel moved human slow because Dean saw him before he took them through time and space back to Dean’s motel room.

“You must stop him.” Castiel was standing too close, but Dean didn’t move back this time. He was still reeling from everything he found out tonight – his mother’s secret past and her culpability in unleashing demonic forces upon the Winchesters to seeing Sam for who he became without Dean at his side. Murtaugh was right. He really was too old for this shit.