Marked has genre Paranormal romanceParanormal romance has examples: Undead and UnwedUndead and Unwed is written by MaryJanice Davidson
[Human]: I like a book called  Marked. do you have something similar? [Assistant]: I bet I do.  Do you like Marked because it's a Paranormal romance? [Human]: yes that is correct what do you have similar? 
Check out Forbidden Love. It's written by Mary Janice Davidson about werewolves.