What is Crusty Face?
1.
The face that one makes when feeling completely embarrassed, otherwise known as
Megan: Hey you guys... Did you see that really pretty girl totally shoot down that loser?
Jackie: Yeah.
Abbey: Totally
All three: CRUSTY FACE!
See
2.
when your face gets so dried that it begins to crust and crumble; crusting of the face.
Ew... put some lotion on your face, you look like Erica Rosenbloom!