Shadowhunter for life
Stiles didn't know this, but he is a shadow hunter. He finds out that he is a shadow hunter when he called his cousin, Clary. He was broken and tired of his life. He was kicked out of the pack and his dad was killed, he wasn't sure by what though.
He does everything he can to be the best shadow hunter out there, and he does. He goes back to Beacon hills with his new family a year later.
This story starts in season five, and this is a Stalec fanfic, obviously.