A Marriage of Undead Inconvenience by Stephanie Burgis

Margaret Dunhaven may have been forced into marriage with the sinister vampire lord of Shadowcroft Manor to fulfill a family obligation, but she’s not about to stay trapped there for long. The beastly man doesn’t even have any decent tea leaves in his kitchen!
However, when she realizes that she’s not the only one who’s been forced into this marital union, it’s time to join forces with her unwanted new husband. If they can combine her scholarly skills with his ancient history, then, working together, they might just manage to reclaim her inheritance, break his curse, and find their freedom.
…Just so long as they don’t fall in love along the way.
A witty and sparkling gothic fantasy novella that puts a new twist on Beauty and the Beast in an alternate-history version of late 19th century England.