Disclaimer: I don't own Supernatural; I leave that to creator, Eric Kripke.
Dean watched Castiel back away from Sam. "What the-?" Dean said as Castiel hit the wall.
"Dean," Sam said. "I don't see Lucifer anymore."
"That's great, Sam," Dean said, "but I'm afraid Cas is."
Sam looked over at Castiel. "I'm afraid you're right," Sam said. "I'll leave you alone so you can deal with him."
"Thanks, Sam," Dean said as Sam left the room.
Castiel sighed with relief. "I'm glad Lucifer's gone now," he said.
"Cas, Lucifer didn't just walk out of here," Dean told him. "That was my brother. You know, Sam, the one who's been hallucinating Lucifer?"
"When I shifted it to me," Castiel said with realization, "I'm seeing his hallucination. He was hallucinating Lucifer?" He looked at Dean.
Dean nodded. "He was," Dean said.
Castiel walked over to the bed and sat down. "I can live with that burden, Dean, as long as you have your brother back," Castiel replied. "And you have to clean up my little problem."
"You call Leviathan a little problem?" Dean asked and then held up his hand so Castiel wouldn't argue with him. "Never mind. Cas, you need stay here because you're hallucinating Lucifer."
Meg rounded the corner and leaned against the doorjamb. "I'll watch out for him, Dean," Meg told him. "So Crowley won't get his hands on him."
Dean looked up at Meg. "I doubt if that would be a problem," he said. "Cas would just use his angel mojo to deal with them." He gave Castiel a smile.
"But I do need someone to watch out for me," Castiel told Dean. "I pissed off a lot people that I didn't know I pissed off."
"I'll be able to watch the crazies," Meg said, "and watch him so he doesn't think that one of the other patients is Lucifer and use his angel mojo on them."
Dean nodded. "I don't like this," Dean said, "but it makes the most sense."
"I'll be alright, Dean," Castiel replied, "with Meg. I'll be alright."
Dean nodded and turned to Meg. "You have my number if anything happens?" Dean asked.
Meg nodded. "I've got him," Meg said. "You go deal with Levithan; I'll deal with Cas. It's been fixed, so I've got a job here."
Dean got up, started to walk to the door, and to look at Castiel. "Cas, I'm just a phone call away if you need anything," Dean said and then left the room. It was the hardest thing in the world to leave the one person who had brought him back from perdition-who had saved him from an eternity of hell, but he and Sam had Dick to deal with and to find out what the hell Dick Roman is doing and what his plans are.