aniki
I've just finished Elder Race by Adrian Tchaikovsky, and thoroughly enjoyed it.
It's about a princess trying to prove her worth by recruiting a wizard to help defeat a demon.
Except the world they're on is a human terraforming colony, now post- (or pre-?) technological, thousands of years in the future. The "wizard" is an anthropologist from a later, more advanced period of Earth history than the original colonists, who spends most of his millennia in stasis while waiting for communications from Earth.
The chapters alternate between third-person fantasy from the princess' perspective, all flowery formal language, and a much more conversational first-person sci-fi for the "sorcerer". Language differences mean that the sorcerer can't explain that he's just a scientist and that his "familiar" is a robot, so he's mostly pretty grumpy about being dragged on a quest by an old friend's great-great granddaughter.