Forbidden Hidden Love (Teen Wolf)(Book 1)

"How could I resist those fangs?" she whispered, giving him another kiss.
"Why didn't you run when I first showed you?"
"Because you were honest from the start."

Fionnuala Isolde Stilinski, Stiles' twin sister, has been in a secret relationship with Derek Hale since summer started. Will their forbidden love for each other be found out? And if so, will she still be able to be with him?