Just a quick one that I wrote in the car to cure my boredom.

AN: Something isn't right with Sam.

Warnings: mild language

Disclaimer: I don't own these attractive people

Dean woke during the night sensing something wrong. He couldn't but his finger on it but he knew that there was something not quite right.

Grabbing his gun from beneath his pillow, he silently padded out of his bedroom down the hallway towards the library. He frowned seeing Sam bent over a book and continuously running his hands through his hair.

His and Sam's relationship had been stretched recently due to the whole Gadreel experience and Dean getting the mark of Cain. Sam still hadn't forgiven Dean for saving him and that cut his big brother deeply; more than he would care to admit. Dean understood that he had upset Sam by tricking him and lying to him through his teeth, but he would be the first to admit that he would do it again.

Dean continued to step closer to his unsuspecting brother.

"What you doing there?" He asked startling Sam and causing him to knock his book onto the floor.

"Dean?" He said, forcing a smile onto his face. "Why are you awake?"

"I just had a bad feeling," Dean admitted. "What are you doing up?"

"Err..." Sam hesitated. "Just reading."

"At..." Dean glanced at his watch. "Three in the morning?"

"Yeah," Sam laughed nervously causing Dean to frown.

"Sammy?"

"What?"

"You feeling okay?" Dean asked and reached towards Sam, causing him to take a step back.

"Of course, Dean. Why wouldn't I be?"

"You're just acting weird," Dean told him.

Sam laughed and shook his head. "I knew it wouldn't be long until you figured it out."

With that, Dean was sent crashing into one of the bookcases behind him. He groaned in pain and rolled onto his side to get a better look at Sam when he noticed his brother's black eyes.

"How long have you been in him?" He spat angrily.

"Not long after you managed to get that angel out of him," the demon chuckled. "Guess this just isn't Sammy's year. But he knows he's being possessed alright. He's inside here," the demon tapped Sam's temple. "Screaming and begging me not to hurt you."

"How did you even manage to get in here without me noticing?" Dean asked and shuffled back across the floor.

"Don't you remember that I was friends with those 'Men of Letters' assholes?" The demon smirked.

"Abaddon?" Dean gasped.

She laughed and couched in front of Dean.

"I don't think you realise what a brilliant opportunity you opened up for me, Dean." Abaddon grinned widely. "You burnt off Sam's tattoo and I thought 'hey, why don't I take this hot body and use it against Dean?' I know you're trying to kill me, but could you really do that with your poor little brother trapped in here?"

"I've done it before," Dean growled remembering when he let Sam sacrifice himself by throwing himself into hell while Lucifer possessed him.

Abaddon frowned in Sam's body and Dean used this distraction to kick her in the stomach, sending her onto her back.

"Sorry Sammy," he apologised as he punched Abaddon across the face, knocking her out.

Dean lifted Sam and threw him over his shoulder. He head towards the dungeon where Crowley used to reside and chained Sam to the chair. He wondered how many more time he would have to tie his little brother up in order to free him from his own body. First an average demon when Sam was a teenager, then Meg, then Gadreel and Crowley. Dean vowed that this would never happen again.

"Cas!" Dean yelled hoping that the angel could hear him. "We've got a problem!"

Dean was filled with relief when the angel appeared before him.

"What seems to be the problem, Dean?" Cas asked, frowning at the limp figure of Sam tied to the chair.

"Abaddon," Dean snarled. "She's possessing Sam because I'm a stupid bastard and forgot to remind Sam to get a new tattoo."

"Dean, this isn't your fault." Cas told him and laid a hand on his friend's arm.

"Anyway," Dean swallowed and shook his head. "We need to get this bitch out of him."

"I'm not sure that can be done." Cas told him.

"What do you mean 'you're not sure it can be done'?" Dean asked angrily.

"Abaddon isn't your average demon," Cas said. "She is a knight of hell, one of Lucifer's first. I'm not sure that a simple exorcism will be enough to get rid of her."

"Well don't sugar coat it," Dean turned away, running a hand down his face.

"Maybe we should summon Crowley," Cas suggested. "He is that king so maybe he will know some way to save your brother."

"No," Dean snapped and span to face Cas. "He will just try to kill her and that won't help Sam."

"You know that the longer I'm inside your brother, the worse he will be when you finally get me out." Abaddon's voice, masked by Sam's, ran through the dungeon. "I'd get to it if I were you."

Dean glared at her and began to speak the exorcism.

"Exorcizamus te, Omnis Immundus Spiritus, Omnis Satanica Potestas, Omnis Incursio Infernalis Adversarii, Omnis Congregatio et Secta Diabolica, Ergo Draco Maledicte, Ut Ecclesiam Tuam Secura, Tibi Facias Libertate Servire, Te Rogamus, Audi Nos!"

Surprisingly, Sam let out the most horrifying scream as the black smoke left his mouth and flew out of the bunker. Dean stared in disbelief before hurrying to Sam's side and freeing him of the chains.

"Dean?" Sam croaked and look at his brother through glazed eyes.

"You're okay, Sammy." Dean pulled Sam into his arms and held him close. "I'm so sorry, Sammy. It's over now. I promise it won't happen again."

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