Looking for a fic

[frostfire_17]

So all I remember about this story is that Jim and Blair have just gotten together, and Jim has had zero gay experience at all before now, and there's a point where they're talking about having sex, and he volunteers to bottom. And Blair has this realization that Jim thinks that bottoming is just a nice thing to do for the guy on top, and has no idea that there's actually something to be gotten out of it for its own sake. And so Blair resolves to blow Jim's mind, and then (of course) proceeds to do so. Anyone?

Thanks in advance!

ETA: FOUND! by the lovely enigmaticblues: it is Waking, by Resonant.