What's more likely? That Gwenaëlle, she of the pile of anatomy books and attentive interest in every aspect of his job that he'll share with her, who has taken an active and marked interest in his area of expertise and expressed consistently her trust in his competence and knowledge, has abruptly decided in this one specific thing to decide to dig her heels in about anything unfamiliar to the average peasant of the Marches,

or that she has simply got exactly what she wanted out of this exchange, at the low cost of a little playacting?

Yeah, it's that second one. The prudish distance he's keeping is just a concession to the fact that she has, in the largest part, totally won.

“I can take my chemise off if that makes it easier,” sounds so reasonable, the way that she says it. Reasonably.