Sam clears his throat, then speaks.
"So…you're saying you're on our side because Dean tortured you?" He can't help the incredulous tone that enters his voice. How exactly was he supposed to take that? Wasn't this some sort of twisted…Stockholm syndrome type situation? But did it count if she was a demon?
And what if she was just another Ruby?
Annie looks irritated at the question. "No," she says. "I'm on your side because Dean taught me how to torture."
Dean's expression becomes even more horrified at that—but not with shock, Sam thinks. More with realization of something he's tried extremely hard to forget. Sam can relate—on the trying to forget part.
He hasn't quite caught up with the 'my brother taught a teenage girl how to torture' part. He probably won't ever wrap his head around that.
"He's the reason I became a demon," she continues. "So, since my human dad was shitty anyway, Dean's my dad."
He's the reason I became a demon. Sam stares at Dean, trying to gauge his reaction to that. Dean still hasn't spoken a single word. In fact, Sam thinks he might be going into shock. Forty years of Hell could definitely give a guy PTSD, and Sam knew Dean had panic attacks and tried to pass it off as normal when Sam asked about it.
Sam pauses in his rambling trail of thought, and wonders if he's in shock too, though maybe not to the point Dean is.
"Hey, Dad, you alright?" Annie asks, and a part of Sam laughs at the incredulity of it all. A demon, calling Dean 'Dad', and asking him if he was alright. And Sam thought he was the one with demon issues.
"Don't," Dean finally says, and Sam attempts to pull himself back into reality.
You call this reality? Internal Dean says.
"Don't what, Dad?" Annie asks in confusion. Dean's head snaps up, and he finally looks Annie in the face, really looking at her, not just staring at some horrific memory of Hell.
"Don't call me that. I'm not your Dad. I tortured you. I made you torture. I'm not your Dad—"
"I'm not the crying girl I was when you first got me," Annie interrupts him. "I'm a demon, and as a demon, my father is you, and my loyalty is to you. You were probably the only good soul in Hell that was assigned to my rack, and you're the reason I'm still coherent, even as a demon that's only a few Hell-decades old."
Hell-decades. Dean tortured for years, in Hell, and Sam sometimes forgets that times passes differently down there—it was only four months for him. The worst four months of his life, yes, but still only four months. Not four decades.
Dean had been down there for that long, and this once-girl for even longer. He knew being tortured had been hard for Dean, even as a seasoned and experienced hunter—he can't imagine what it would've been like for an abused teenage girl.
He doesn't want to imagine.