His incredulous reaction makes her smile. Of course she knows he trusts her, but trusting her to attempt stitches on him when she's been shown how to do them a mere handful of times - well, actually, on second thought, that seems just the kind of thing he'd sit and tolerate from her, even if it was just for practice.
That thought has her looking amused, and she skirts by him in the small space, determinedly not focusing on the clean soapy smell of him or the dampness left behind by his not-towel, because asking him to lay down on her bed is already enough that she's sure he'll squirm. So she'll try to keep it professional - for now, until she gets these stitches in. "Just gonna wash my hands," she says, which she's sure is something these boys wouldn't have thought of themselves, considering their oil rags and duct tape remedies.
At the little sink in the kitchen her hands make the water a rusty orange color until it runs clear, and she checks that the wound on her arm has stopped bleeding freely before she returns to where Sarge is sitting. Sets the medical supply kit down and then kneels on the bed, her expression prompting him to lay back. She knows that he's still hyped up from all that happened to him in La Quinta, can see the way he's even more tense than usual, the way his eyes have been scanning for threats since the moment they met at the gates. So instead of diving in to care for the wound, she rests one hand briefly on the front of his shoulder, like she might some skittish thing, before she takes out the suture kit and supplies, a sterile drape on the bed, gauze ready if it bleeds. She mutes a smile, looking over the wound and then at his face. "I hope you're not ticklish, sweetheart," she says, before her hands alight on him.