My High Horse Czar - The Russian Witch's Curse, #3

Adriana's stuck between a rock and a very hard, very dangerous place. It's not the first time she's ever been in trouble, but it is the worst. When her twin sister calls and tells her that Mirdza's going to be killed unless Adriana surrenders herself in half an hour, she figures she doesn't have much to lose. But Adriana has no idea how much excitement her future holds, or whose protection she's about to awaken.
The scrappy fighter who has vowed never to date or marry is about to meet her match in the highest horse-shifter in existence-the displaced Czar of Russia himself, Alexei Romanov.