Pawn of the Cruel Princess By Rebecca F. Kenney

In a power play against her older sister, fierce princess Ruelle (who likes torture a little too much) lays claim to the young enemy Captain her father has taken prisoner. The captive will be Ruelle’s first pleasure thrall, and she plans to flaunt her ownership of him at Summerglee, a debauched retreat for the young nobility of the kingdom. But the handsome prisoner has his own plans.

Trigger warnings are available on the author’s website and in the front matter of the book.