Sam has no idea what's going on, other than that it has something to do with the time Dean spent in Hell.
"Dean, what's going on?" He asks in a low voice. Dean turns to look at him—Sam hasn't seen his eyes so haunted since back when he first got dragged out of Hell.
"Meg called Alastair 'Dad', Sammy," he says. "Connect the dots."
Sam blinks and thinks. He reaches a conclusion in seconds. Meg had called Alastair 'Father' because he had been the one to torture her and indoctrinate her into torture. The demon—Lily-Anne, Annie—called Dean 'Dad'.
Dean had tortured for ten of his Hell years.
"Oh," Sam says. It's all he can say, really. The demon—Annie—lifts a brow.
"So, Dad, I'm on your side," she says. "Because Lucifer is overrated and I heard on the grapevine the demons sucking up to him are dropping like flies."
Sam blinks at that unexpected piece of info. Before he can question it, she waves a hand at him.
"He keeps using them for sacrificial spells," she explains. Dean just continues to stare at her in shock.
"Oi, Dad, I followed you out of Hell, and I can be an informant for you," she complains. "Aren't I gonna get a thanks."
"You were sixteen," Dean says suddenly. "You made a deal because you wanted your Dad to stop hurting you, when you were five."
Sam stares at them both. He'd almost forgotten—demons they might be now, but they had once been human too.
"I told you I'd be your new Dad," Dean continues. "You broke in a month."
"You were sixteen," he repeats, like a broken record. Sam knows he can't even begin to understand the crushing guilt Dean probably feels right now.
"Calm down," Annie says. "You were a better Dad then mine, 'ey? 'Least you didn't rape me," she grumbles.
Dean looks like he's about to be sick, and Sam feels the same.
The pie lays forgotten on the bench.