Letting that laugh escape wouldn’t have been the worst thing; he already knows that feeling Gwenaëlle laugh from inside her is one of his favourite, ridiculous, utterly unplanned sensations of all time, but at the moment they’re working very hard on solving a very important puzzle together and probably need to focus on it —

God, their lives.

And in terms of science, experimentation, seeing what works and what doesn’t, they could do far worse. And so Stephen gamely obliges; like pulling her hair, that anchoring touch and now subtle sensors in the wings being able to tell how far away he is, where his arm is placed. He splays his hand in that strip between the wings, palm pressing down on Gwenaëlle’s spine (another place where she was injured and wasn’t, no scar to mark the memory of Granitefell), weight on vertebrae, and he starts to move once more.

“How’s that,” and his voice is raw; on his knees behind her, pulling out only to rock back in again, accompanied by that slick slide.