Power's Seekers (Supernatural and Teen Wolf)

"Get this," Sam said, motioning to Dean and Caterina. "There's a town in California, Beacon Hills, where there have been over twenty occurrences of strange or supernatural events. These go back for decades, but people are reporting fanged and clawed monsters almost every other day now."
Dean frowned. "You're kidding. How haven't we heard about this?"
"The Sheriff's department has hushed most of it up. What they haven't been able to hide, though, is the number of murders that have been piling up over the last two years."
"California or bust!" Caterina sang.
--
Set between season 4 and 5 of Teen Wolf and post season 9 of Supernatural, following the timeline set in my other novels Hell's Protege and Heaven's Savior. Those two stories are not a prerequisite, but may help in your understanding some.