Taken by Nightfall - The Midnight Valley Saga, #1

Midnight Valley is known for the many cold case murders and disappearances that have taken place within its city limits. It should have come to no surprise to Violet Miller that there was more to these cases than met the eye. In her efforts to protect a friend from the mysterious creatures of the forests and keep him from turning into a monster himself, Violet visits the secretive group called the Exigency, befriends a werewolf and endangers her own life.
But it might already be too late.