El Corazón del Lobo

Derek drove back into Beacon Hills on a Tuesday morning seven years after he had left it last with one single thought:

“Why am I doing this?”

But in his heart, Derek knew exactly why.

(In which Stiles suffers temporary memory loss and any serious emotional trauma could give him permanent damage so Scott calls Derek to come back and fake like he and Stiles are still together so that Stiles can heal)