Disclaimer: I do not own Supernatural or Twilight.
AU. Wincest though unrelated in this.

Chapter 1

Sam ran quickly through the trees, instinctively moving so that he wouldn't actually run into any of them. He wasn't sure why he felt drawn to the area but he knew better than to ignore those instincts. At the last second he jumped, catching onto a branch and using it to pull himself into the tree. He peered down into the clearing, trying to work out what was going on and then the wind shifted and he felt like banging his head into the tree. Vampires...he hated vampires! He gathered himself, ready to attack and take them by surprise but then he stopped and just watched, trying to figure out what they were doing. Then he realised, they were in the process of changing the third figure. Poor guy was screaming, thrashing as one of the vampires bit into his wrist and drank form it for a bit before moving to another vein. The other vampire appeared to be standing watch. It was too late for the guy; no matter what Sam did the poor man would change, better for him to get as much venom into his system as possible to make the change quicker. Sam wasn't an indiscriminate hunter, he would only take out the new vampire if he started killing. Once they were done with their victim Sam moved, dropping from his tree and attacking instantly, they never had a chance.

Once done he set the parts alight and then crouched next to the slowly changing male. He looked a bit shorter than Sam, his blonde hair cut almost military short and he was pretty well built and tanned, not that the tan would survive past the change. The guy screamed and his eyes opened, revealing pain filled green orbs. Sam reached out to tap his cheek, trying to get him to focus and it was obvious he was trying.

"My name's Sam, I'm here to help you. Can you understand?" Sam asked and he got a nod even as the guy clenched his jaw to hold in another scream.
"What's your name?" Sam asked and the man shut his eyes, panting for air.

"D...De..an." Was ground out and Sam gently brushed his fingers through sweat damp hair.

"You're going to be okay Dean. You need to listen closely. I know it hurts, more than anything but the pain will eventually stop. It will last for a few days. You need to do something while this is happening. Dean you need to focus on reliving your memories, over and over. Keep them as clear as you can in your mind. Can you do that?" Sam asked and got another pained nod.
"Good, that's good. I've got to move you now and it'll hurt but we can't stay here. Try to sleep if you can." Sam told him as he scooped Dean up and then stood, Dean trying not to scream at the movement. Sam moved as quickly but gently as he could as he headed deeper into the woods, looking for somewhere to hide Dean for the next few days. An abandoned cabin was too much to hope for but he did find a nice dry, empty cave that'd fit them both. He sat beside Dean and took his hand, talking softly to him to try and help Dean cope with the pain.

Dean spent the next three days screaming and writhing in agony with Sam watching over him. He hoped Dean managed to keep most of his memories, especially of whether or not there were more vampires than the two who had been changing him. Sam held his hand as the venom reached Dean's heart, his green eyes wide with terror and pain.

"It's okay, it's almost over." Sam whispered as Dean's back arched and then he slumped, to all appearances dead. Sam gently stroked over Dean's face, hoping to keep him calm and now red eyes slowly flickered open and then Dean was moving. He scrambled to the back of the cave, eyes searching wildly as he crouched defensively.
"Just relax Dean, you're safe." Sam soothed and red eyes fixed on him.
"Do you remember what happened?" Sam asked and the vampire licked its lips, its eyes narrowing in confusion.

"Sam?" Was the hesitant reply and Sam smiled, nodding.

"Yeah, it's me." Sam held out a hand and Dean slowly edged closer until he could take the hand.
"There you go, it's alright. Hard to concentrate isn't it? Is your throat burning?" Sam asked and Dean's hand went to his throat.

"Yes." He answered, looking around.
"You smell funny." Dean commented and Sam laughed.

"Yeah, I bet I do. Lets you know not to try and eat me." Sam told him with a grin.

"Eat you... need something Sam, please."

"Okay, we'll go find you something." Sam tugged him to his feet and then out of the cave. There was no way he was going to let Dean hunt down a human to eat so he'd have to do with an animal of some sort. He ran with Dean, watching him carefully as he hunted for the first time. Thankfully Sam couldn't sense any humans around but there was a mountain lion nearby that he steered Dean towards and then he pulled back as Dean attacked it, burying his teeth into its throat and beginning to drink. Sam leant against a nearby tree to keep watch, smiling when Dean looked up at him. He knew Dean would be pretty much lost to his thirst for around a year and for some reason he found himself wanting to stick around and help him through it.

After Dean was done Sam led him to a nearby stream to clean up and then they headed back to the cave where Sam realised they had a problem. He needed sleep, Dean didn't. The last thing he wanted was for Dean to wander off and kill someone while he was asleep. He could go a long time without sleep but eventually... then he grinned, that would work. Sam lay down with his back against the wall and then held his arms out to Dean. The new vampire hesitantly crept closer and then let Sam tug him into his embrace. Sam held him, running gentle fingers through Dean's hair and he felt him slowly relax. Sam cradled the hard, cold body to his own and smiled when Dean burrowed closer to his warmth.

"It's okay Dean, I'm going to look after you." He promised softly and the vampire fixed crimson eyes onto him.

"What's happened to me?" Dean asked and Sam was happy that he realised something had happened to him. He'd seen newborns so lost to the thirst that they didn't even remember their own names let alone wonder why they wanted blood.

"You were attacked and bitten Dean. You're a vampire now. You'll need blood for as long as you're around but it doesn't have to be human. If you bite a human they will either die or become a vampire and I can't let you do that." Sam explained and then waited to see how much Dean understood.

"Vampire?" Dean frowned, swallowing hard.
"But...not real."

"Yeah they are, so are a lot of other things people think are myths. I hunt the ones that hurt people."

"Will you hunt me?"

"Don't want to, that's why I'm staying with you. I'm going to help you Dean." Sam told him and Dean nodded.

"I want to go home." Dean whispered softly and Sam closed his eyes in pain, knowing it could never happen.

"I know, I wish you could but you can't Dean. You don't look human anymore, not enough to fool anyone who knew you." Sam explained gently and Dean looked down but nodded.
"How much do you remember?" Sam asked but he saw Dean's attention beginning to wander...and then a pale hand went to his throat.

"Yes." Dean answered and Sam stood, leading Dean out to hunt again.

Sam watched Dean as he feasted on his dinner; thankfully Dean only needed the blood so Sam could cook the rest for his own dinner later. They'd easily fallen into a pattern and Dean was settling slowly but surely. He'd only had to pin Dean telekinetically once when some poor hikers had gotten a bit too close but after that it had taken weeks for Dean to stop being scared of him. Dean looked to him like he probably would the one who had changed him and it was a lot more responsibility than Sam was used to anymore but it felt nice to be the centre of someone's world for a change. He'd even gotten Dean used to lying quietly in his arms when Sam needed to sleep. He'd found Dean staring at him before he fell asleep and still doing it when he woke and often wondered what the vampire thought about during that time but he wouldn't ask.

Sam had only left Dean alone once and that had been to return to the Impala for his bag. Unlike Dean, Sam did sweat so wearing the one outfit for months on end? Not a good idea. He hadn't left again though, Dean had been panicked and almost violent when he'd returned, it had taken hours and a hunt to calm Dean down again and then he'd spent the night curled up in Sam's arms...the first time he'd initiated such a thing. Sam knew Dean was confused and scared...when he could concentrate past being thirsty. He hoped that would gradually go away, they couldn't live in the woods forever. Dean would eventually have to learn to ignore the lure of blood enough to move about in towns.

"Sam?" Dean called and Sam smiled at him before laughing at the site Dean made, tufts of fur stuck to his face by blood.

"You need to wash up Dean. I think we both could do with it actually." Sam said and he led the way back to the stream so they could clean up. They splashed around in the water for a while, the freezing water having no affect on Dean and taking a while to do so to Sam. They flopped down on the bank, content to lay and dry out in the sun, Dean staring at his sparkling skin as he always did when he was in the sun.

"I sparkle." Dean whispered and Sam chuckled, rolling to his side and leaning up on one elbow.

"Yep, all vampires do. That's why you need to stay out of the sun after we leave here." Sam explained, reaching out to run his fingers through Dean's hair and smiling when Dean moved closer.

"Leave?" Dean asked, looking up at him and Sam was interested to see that Dean's eyes were changing colour, the red slowly fading. He'd never seen a vampire with anything but red eyes, unless they were black from hunger. Maybe the animal blood was why his eyes were changing?

"We won't stay here forever Dean. Once I'm sure you can control yourself around people we'll hit the road, find a house to live in or something." Sam explained and Dean frowned but nodded.

"You won't leave me?" Dean asked quietly and Sam pulled Dean into his arms, rolling back onto his back so the vampire was cradled against his chest. Dean clung to him and Sam soothed him.

"Never Dean. You're all I have. I've been alone since my Dad and Uncle died and I thought I was fine till I found you." Sam whispered and Dean relaxed, smiling slightly at knowing Sam wouldn't leave him. He curled up on Sam's chest, knowing that his weight didn't bother Sam at all and he almost purred when Sam began running his fingers through his hair.

Sam laughed as he chased Dean through the trees, letting the vampire stay ahead of him for the fun of it. It was great that Dean was laughing too as they ran, he hadn't heard Dean laugh at all before. Dean's eyes colour had finally settled too and Sam had to admit he liked the soft golden colour. Sam as hoping they'd be able to leave soon since Dean had settled down a lot recently, although he was still very clingy. His head seemed a lot clearer and he could go nearly a day without hunting so Sam figured another four months or so and they could try testing Dean's resistance. Of course as soon as he decided that he picked up a group of people headed their way and the wind shifted before he could call out to Dean.

Sam picked up the pace but then he saw Dean slam to a stop and freeze completely, hands fisted at his side and eyes slammed shut. Dean was growling slightly but was obviously doing his best to fight the temptation.

"Easy Dean, you're doing great. Give me your hand and we'll get further away." Sam said and Dean jerkily raised his arm. Sam grasped his hand and then tugged, making Dean move with him deeper into the woods and away from the humans. Sam stopped when they were well out of range and then wrapped his arms around Dean who buried his face in Sam's neck, inhaling his scent.
"It's okay now. You did great Dean, I'm so proud of you." He soothed and Dean slowly raised his head, revealing his eyes had gone black from hunger.

"It smelt so good." He whimpered and Sam nodded.

"It always is, the point is you didn't go after them." Sam assured him and Dean nodded.
"Come on, let's get some diner."

"It stinks when you cook it." Dean wrinkled his nose and Sam laughed.

"Yeah but I don't think I could stomach it raw." He took off and Dean followed quickly.