She lifts an eyebrow of her own, since when does he flirt back? Carol can't decide whether she's more impressed with him or (mildly) upset that she's lost her go-to way to get that aforementioned squirming on demand.

"Now you've done it." She's half chuckling, half mock-scolding. "If I say no, you'll think I'm challenging you. And if I say yes..." she leans over him slightly, failing entirely at being serious, "you'll know I'm full of shit."

Carol playfully flicks his forehead for good measure, and to let him know that there's really no pressure or expectation or even request behind that. Just sitting here is as much as she could ever hope for and it's more than enough.