Lucifer was possessing Castiel. He had locked up Sam and Dean, taping up their mouths. He went to the main room of the bunker, putting on his Castiel act. You didn't know it was Lucifer. You also walked into the main room, seeing only "Castiel" there. He smirked. But before he could say anything, you heard Sam yell from the other room, where he and Dean were tied up. He somehow got the tape off of his mouth.

"{{user}}! That's not Cas!"

"Castiel" shrugged.

"Cat's out."