The Wolf That Heard Crying by grimm
Summary: There was someone in Derek's house. He was on his way back from a hunt, licking blood from his muzzle when he heard the sound of smashing wood coming from inside. Derek snarled quietly, leaping up onto the back deck without a sound. He paused in the doorway to the living room, eyes burning red in the dim light. The boy whacking the wall with a moldy piece of timber was different than the ones who had come before. He wasn't laughing, wasn't enjoying himself as pieces of rotten flew from both the wall and the wood in his hands. He smelled of sadness and desperation and anger, and when the piece of wood in his hands finally splintered the boy sank to his knees and cried.
.Stiles/Derek, NC-17, wolf!Derek, angst, hurt/comfort, knotting, injury, AU.
http://archiveofourown.org/works/754301