I, Strahd: The War Against Azalin
By P.N. Elrod
Series: Ravenloft Books

"The young and idealistic brother to the war-hardened Strahd von Zarovich loves beautiful Tatyana, but so does Strahd. To win her hand, Strahd will do anything--even enter a pact with death and seal it with his brother's blood." (summary from Amazon.com)

Paperback Info: ISBN 0786907541, TSR Hobbies