Women Warriors at the River of Blood

From Memory Alpha, the free Star Trek reference.

Women Warriors at the River of Blood is a Klingon romance novel, with a more "vigorous" story than its typical Human counterparts. Its main characters are Rorg and M'Nea.

Excerpt:

Rorg turned his fierce eye upon her, and M'Nea felt her heart begin to quicken, even as her hand went to her dagger. She had intended to plunge it into his throat, but something about him made her hesitate.

Tom Paris caught B'Elanna Torres reading this book in 2373, who defended it as "escapist reading". (VOY: "Real Life")