A study in the eyebrows of a Hale

Derek may not be able to talk about his emotions, but he doesn't need to, his eyebrows do that for him. Stiles decides to document these looks and their meanings, everything ranging from fear to happiness and something else that Stiles is too oblivious to work out.

Or the five times Stiles knew what Derek was feeling without him having to say anything and the one time Derek had to spell it out, literally.