This is the last chapter, I do plan to make an other to complete this one (or maybe a completely different one before I don't know yet) when I have time ! I hope you enjoyed it :)

Lucifer. So it worked. The sound of his voice, Sam wanted to puke and he would have done it if he wasn't so resolute to save Dean. He looked up, obviously he did not miss him, he hated when Lucifer made fun of him. The outcast of Heaven had been in his head and Sam wasn't really fond of him, well he hated him.

"Come on Sammy ! Don't tell me you're still angry because of what happened between us ? I thought it was really good, we bounded !" Lucifer had a grin on his face and Castiel could see that Sam wasn't feeling well.

"We need to talk Lucifer."

"Oh Castiel ! Long time no see, how's your mojo going ? Not very well apparently." His smile grew wider and wider, he knew he was getting into their heads. Castiel needed to sort out his thoughts and his mind before his brother could gain the upper hand and it seemed that Sam had the same idea.

"You need to help us." Sam said.

"And I thought you broke me out because you wanted to see me, I'm disappointed Sammy." His face lighted up at that precise moment. "Are you here to bargain by any chance ?"

"Maybe."

"I like what you're telling me !"

"And I don't like where this is going Sam." Castiel stepped in.

"It's because we have no other choice Cas."

"By the way kids, where is Michael's annoying vessel ? Did you lock him in a cage as well ?" Lucifer was laughing, he definitely knew what to say.

"That's why we're here." Just the fact that Lucifer mentioned Dean annoyed him already, what will it be when they talk about the Mark. Sam grabbed the First Blade on the table and showed it to his tormentor. "You need to take the Mark off him !"

"I see what happened ! Big bro got into trouble and you want to be the hero for once. What do I get ?"

"Name your price."

Castiel was standing back while Sam spoke to Lucifer, he didn't like the idea and he absolutely hated what will come next. Dean will never forgive him for letting it happen, truth is, Castiel will never forgive himself as well.

"I would like a yes very very very much !"

Sam turned white as a sheet, he figured out that it would be the price to pay but hearing it from Lucifer's mouth was different. He was scared, he was powerless and he knew it was the only way to save him but there was a thing that Sam was sure about, Dean will save him. He didn't know how or when but he will do it.

"I will say yes once you got rid of the Mark."

"I think we have a deal !" The fallen angel had the happiest expression that someone could have on his face. "When do we start ?"

"We have to go back where Dean is but if you want me to honour our deal, you must listen to everything we say and don't try anything." Sam was trying to keep Lucifer under control but he knew if he wanted to escape or to kill them, nothing was preventing the fallen angel to do it.

"Sammy, don't you trust me ?" Lucifer was still smiling. Of course he kept on smiling, he finally acquired what he desired, Sam's benediction, Sam's approval, Sam's yes.

"We have to go now." Cas decided to finally speak up, he wanted to save Dean as quick as possible, even if it meant to loose Sam. He was sure that Dean wouldn't agree and would want to kill him afterwards but there is something else he was sure about : he would save Sam. No matter what he will save him.

"You're right. We gotta go, it's a long drive."

"What ? We have to drive ? Poor you, let's zap to Dean !" In a snap they were back at the bunker.

"How did you ..."

"I've been inside your head my friend remember ? And don't worry I brought everything back with us." He pointed at Cas, behind him was the First Blade and the Rings. "I've even brought your precious little car ! I am so kind, you should love me more."

Castiel was already on his way to Dean's room, he opened the door.

"Dean, please do not get upset."

"What did you do Cas ? Cas !"

"We had no other choice, I'm sorry Dean, I'm sorry for everything. Just know that Sam trusts you and he knows you'll do all you can to save him."

Dean was scared, he was a demon but Sam was still is little brother.

"Good morning Vietnam !"

The older Winchester couldn't believe what he just saw, are they joking, are they fooling him ? No, it couldn't be possible nor true, the devil was here, Lucifer was here.

"What did you do ?" he yelled at Sam who just entered the room. "You really thought I was gonna accept that ! I ain't buying it !"

"No one is asking if you agree or not. I'm doing it and that's the end of it."

Dean was angry like he's never been before, the urge to kill was even more violent, he didn't have the First Blade with him but there was no difference. His humanity was nearly gone.

"Don't you dare touch me son of a bitch !"

"That's not very nice Dean, Sammy here, asked me very nicely and even made a deal, now I have to cure you even if I honestly think that black eyes suit you better."

"I'm gonna take your head off your body and burn your freakin' wings !"

"Again Dean, not very nice." Lucifer approached Dean and grabbed his arm before the possessed could say anything.

"Done !"

Dean wobbled for a brief instant and took a step out of the trap. As he was stepping out the Devil's trap, the not possessed anymore Winchester nearly puked.

"Not going to vomit are you ?" Lucifer was mocking him.

"Sammy ... Why ?" The expression on his face was filled with pain, sorrow as if he wanted to cry.

"Because I know you'll find a way." His voice broke, Sam wanted to cry but he knew he wouldn't be able to.

"Now now, very touching but Sammy, I'm waiting for a little word." Lucifer didn't want to loose time.

Sam didn't have a choice anymore, he had to say the word he hated the most.

"Yes."

"Here I come ! Say goodbye to your little bro !" As he spoke to Dean, Lucifer switched body, his previous vessel dropped on the floor, dead. "Much better !" Now Sam was talking or rather Lucifer in Sam's body. "I truly prefer your brother, much more comfortable !"

"Get out of his body !" Dean screamed.

"Oh no, I won't do that and you know why ? Because Sammy gave his approval in order to save you. Now I have things to do, if you'll excuse me, I think we shall see each other pretty soon, ciao ciao !" That was it. Lucifer disappeared just like that in Sam's body, Dean couldn't believe it.

"Cas ! What happened ? Why ? Why didn't you leave me ?"

Castiel was standing in a corner, he didn't try to speak or to interfere with what was happening, he knew he couldn't do anything. He also knew that Dean would be angry and would need explanations.

"Dean ..."

"You were supposed to take care of him if something happened, you knew that ! Why did you let it happen ? Why ?" Dean's anger was directed to Castiel, the angel felt his heart breaking again.

"Dean please ... We couldn't loose you, we just couldn't ..."

"And now I've lost my brother !"

"Dean ! Do you think I don't know that ! Sam didn't want to leave you like that and I didn't want to loose you ! What would I do ? Think for a second ! We care about you, I care about you !"

The hunter stopped trying to argue and stared at the angel. He was right, Cas needed Dean but Dean needed Cas too.

"And you know, I talked with Sam and he told that you would react like this but he also knew that you would find a way."

"And how ?"

"I don't know but we'll find a way. But first, what are we going to do with him ?"

Cas pointed at the body, the former vessel was lying on the floor.

"We get rid of him and we start looking for a solution."