When the Werewolves attack the wererabbit sanctuary, Sierra is quickly hidden away. Newly eighteen, she's one of the youngest of the nest and is supposed to be kept hidden until she's old enough to be mated, but she's not hidden.
Instead, she's in the library with no protection at all. Two Werewolves find her and convince the terrified wererabbit that in order to keep her safe, they have to mark her and cover her with their scent and she is naive enough to believe them.
All Sierra knows is that she's never felt this good before as she surrenders to them completely.