Pull-out value is a variable determined by a females attractiveness, and directly correlates to the probability of pulling out. Pull-out value is on a scale from 0-1.
Very attractive; Pull-out value of .90
I mean shes hot I guess; .70
Dude she is homeless; .20
dude 1: "Damn, Ms. Chandler thicker than a bitch"
dude 2: "Hmmm. I'd say her pull-out value is .09"