That makes him chuckle, both because he does find it funny and because the fact that Sophie is trying, in some way, to use humor to diffuse the situation and deal with her own sentiments on the matter means that she's probably going to be fine.

No. She will be fine, if he'll have any say in the matter.

"Intimacy determines one's sympathetic ties to people, places, and objects. In order to keep the curse from activating, all we'll need to do is constantly destroy the magical equivalent of the sympathetic links that you build to people. That will let you get as close to people as you like without fearing that you'll end up harming them."