Slightly steam-punky alternate Europe trapped in a kind of ice age? Different magic system? A some-what magically gifted young woman forcibly married (but not rapey - yay) to a hot, complicated mage? sounds fantastic!
Except for the writing. It was sluggish and bloated. There was a lot of info dumping. I mean, it was okay. And Okay enough (and priced well enough) that I'll continue with the series, because it could be more interesting.
Cat and her cousin, Bee are young ladies in an impoverished, formerly great?, family/House. Through some previous pact, the daughter of the house was forced to be wed to a mage from a big-bad powerful house. the wrong girl was married, the mages were cranky, and then we start the headlong pursuit to escape death (and probably marriage as well). The romancey bits were there, but low key. I kinda heart both Vai and Rory. The girls are OK, and the secondary and tertiary characters were interesting enough.
There's nothing earth shatteringly original about anything going on in the story, but I did like the characterizations. But the bloat... oh the bloat. Oh, and the fact that it's not a complete novel, I at least like my books in series/trilogies to be individual stories.