The rim of excessive ginger fuzz around the outside of a boys lips, creating the illusion of a vagina on the face
'yo, did you see that shaun kid today? He had a hairy smile, creating the illusion of a vagina on the face'
After performing an act of an Oral nature, one usually gets pubic hair stuck between one's teeth.
"Cracking Blow Job love, give us a hairy smile"