She leads him around one of the partition walls through a small kitchenette – as sparsely furnished as the living room – and then round a corner towards where a translucent plastic curtain hangs from ceiling to floor. Dean raises an eyebrow as she pulls back one of the plastic strips to allow him through, the room beyond seeming to him to better befit an industrial warehouse than a medical setting. There are no windows, the room bordered on two sides by plywood partitions and on the other two by cold grey brick, with the plastic sheet forming the only entrance. The gloom lifts slightly when Carter crosses to the wall to flick on a light switch, but the only light source is a single, dim yellow lightbulb hanging by a cable from the ceiling. A plain wooden chair sits just to the right of the entrance and the scent of disinfectant hangs thick in the air. Dean spies a mop and bucket propped against one of the brick walls, beside it a couple of trolleys laden with instruments plus a medical lamp, but what immediately catches his eye is the apparent centrepiece of the room: a single exam table, relatively new looking and upholstered in black vinyl to match the floor. His mouth goes dry when he notices the leather restraints attached.

A chuckle sounds off to his left as Carter notices where he's looking. "Don't worry, I'm not going to be using those today. Unless you're into that."

He scowls as he glances back at her, unable to tell if that was meant to be banter or if she's just mocking him. Either way, it doesn't exactly put him at ease. "I think I'll pass."

She just shrugs. "Can I take your jacket?"

Taken aback, he slips it off and hands it her, for a moment thinking maybe she's actually trying to be polite. Then he sees her not-at-all subtly check out the cash he's put back in the inside pocket.

"Alright, shirt off," she orders, casually draping his jacket over the back of the chair by the door and then crossing to one of the trolleys to wheel it over. "On the exam table, if you don't mind."

Dean can already feel goosebumps forming on his arms, the air in here seeming even colder than the rest of the apartment, but he'll be damned if he says anything. Obediently, he slips off his flannel and t-shirt, and she takes them off him to dump by his jacket as he sits down on the side of the table. His gaze wanders over to the cart she's just rolled across, and aside from the regular equipment like the thermometer and stethoscope lying there, he can't help but notice the tray of surgical instruments beside it. He gets no such reassurance that she isn't planning on using those.

"Alright," Carter finally says, picking up the stethoscope to sling round her neck and snapping on some latex gloves. "Let's get this show on the road, and all that." She gives him no warning of what she's about to do, and the next thing he knows a penlight is in her hand and she's shining it in his eyes. It's unexpected, and he blinks, earning him a cold hand on his forehead and a thumb holding his eyelid open. She doesn't say a word.

He's silent for a couple of seconds as the light moves from side to side, then his curiosity gets the better of him. "I thought you were checking my heart?"

"You said you were a demon," she says, shifting over to his other eye. "I just want to check all bases."

Oh. He can't bring himself to respond to that, scared that if he asks if there's any black in his eyes, the answer might actually be yes. Fortunately, it seems that everything's kosher as she straightens up without comment, putting the penlight down and then picking up another instrument. "Gonna do a blood test too. I want to check your sulfur levels."

Warily, he eyes the syringe and tourniquet she's holding in her hands. Last time he'd been anywhere near a needle, it was Sam injecting him with purified blood to try and purge the demon from him. It's done nothing to make him hate needles any less.

He takes just a second too long in straightening his arm for her, so she does it for him, grabbing his left wrist and roughly pulling to expose the inside of his elbow. He scowls, and despite his discomfort he can't bite his tongue. "What happened to medicine needing a gentle touch?"

He's expecting an equally scathing retort, but her response surprises him. "Sorry, I'm used to dealing with patients that require a bit of rough handling."

That only prompts more questions about what treating demons even involves, but they don't reach his lips before his eyes land on the puncture marks on her own arm again. Tightening the tourniquet around his bicep, she again notices where he's looking. "Don't worry. I've got better aim than it looks."

"Hm." One eyebrow creeps closer to his hairline. "So…you one of those Gregory House types? Drug addict with a brilliant medical mind?"

It's a bold question, especially with the hint of sarcasm, but rather than looking pissed she gives a wry smile. "It's not drugs. Let's call it…on ongoing experiment in organic alchemy."

"Alchemy?"

"Yeah." Her probing fingers find a suitable vein, and she swabs the area with alcohol before prepping the needle. "The application of alchemy to medicine. That's my field."

"And that lends itself to treating demons?" He asks the question then immediately winces as the needle punctures his skin. Hopefully, that wasn't intended as more rough handling.

"Demons make great guinea pigs. You've got a body you can do just about anything to and they'll still be lucid enough to answer questions."

Now that strikes a nerve. He hadn't exactly been expecting to find anyone with anything other than firmly grey morals when he came here, but hearing her say it leaves a bitter taste in his mouth. "Doesn't it bother you there's an actual person in there being possessed? Who's suffering because of the demon you're trying to help?" He doesn't care if that pisses her off. He knows he needs her help. Doesn't mean he has to like it.

Cold eyes settle on him once again as he feels a twinge from the needle in his arm, and he wonders if she just jabbed it deeper deliberately. "Trust me. By the time they get to me, anyone else in that vessel is long gone. The whole reason demons seek my help is that their vessels have passed the point of being able to function like something living."

Whether that makes it better or not, he really doesn't know. In any case, antagonizing her doesn't seem like a good move right now. Exhaling slowly, he says no more and lets his eyes fall to the vial now filling with his blood: a surprisingly fast gush from his vein that forms bubbles as it hits the sides of the tube. It's not exactly pleasant, and he grimaces.

Just a few seconds later, and she's pulling the needle out and pressing a cotton bud to the inside of his arm. "All done. Keep the pressure on that for a sec." He obeys, watching her rip off a strip of tape to secure the dressing in place, and then she shoots him another question. "You cold?"

That takes him by surprise. "What? No, I'm fine."

"Your skin says you're cold." Apparently, she's just noticed his goosebumps.

"No, really. I'm okay."

"I have a thermostat. I can turn it on if you like."

"I guess…" Now he narrows his eyes in confusion, watching her head to the wall to turn on the heating. "Aren't you cold?"

"I don't get cold," she states plainly, crossing back to him without even glancing at his face. That only raises more questions, but right now, he doesn't feel inclined to ask. "Right. Gonna take your pulse. Give me your right arm."

Now's the part where he knows he can't hide the Mark from her, if she somehow hasn't noticed it already. Somewhat hesitantly, he extends his right arm for her, but she digs her fingers into the artery below his thumb and looks at her watch without comment. "Ninety-six beats per minute," she remarks after what Dean's sure can't have been a full sixty seconds. "Nervous, Winchester?"

Again, he can't tell if she's mocking him or not. "Well, your bedside manner could use a little work."

She chuckles. "That's what they said in med school. I mean, I wanted to be a coroner. Never thought it would be an issue."

The statement is far from reassuring, and an uncomfortable thought springs to mind. "Wait…if you've been treating demons that are mostly just dead meatsuits, when was the last time you actually treated someone living?"

"You're asking me to think back a long way, there."

He's sure his pulse thumps a little faster at the words. "So…not many beating hearts?"

"No, actually. This is quite a nice novelty."

An uncomfortable feeling settles in the pit of his stomach, and he finds he's fighting the urge to just get the hell away from here. There's not been a single thing she's done or said since his arrival that has put him at ease.

"Seriously, Dean," she says when she realises he's too caught up in his own thoughts to say anything more. "Ninety-six bpm is an unusually high resting rate. I need to know if it's because of nerves, or something else."

He turns his head to look at her, gritting his teeth when he has to meet her gaze. His reply is cold. "I'm nervous, I think."

There's no change in her expression. "Alright," she says simply, dropping his wrist and crossing to the cart to pick up another instrument. "I'll do your blood pressure then." Her head jerks sharply towards his arm as she brings the cuff back over to him and unslings the stethoscope from her neck. That's when the bombshell drops. "You gonna tell me about that, or just assume I'm an idiot who hasn't noticed?"