it happens around the end of every semester when you, or some other unlucky chump, sits in the campus library on a couch that is way more comfortable than study-focus-appropriate and just stare because even with a laptop and papers scattered before you, there's nothing you can do because of mind-crunch-overload...
guy 1: see that dude over there with that crazy finals face?
A face having characteristics of baggy/tired eyes, acne break outs, oily skin, etc. due to staying up late studying for finals. Basically, you look like shit after studying for finals the night before.
dude1: Hey man, are you feeling OK? You look a little tired.
man2: Yeah, I'm OK. I just pulled an all nighter for my final today.
dude1: It looks like it. You got a case of Finals Face my friend.