A Fuck boy is a boy who got hurt by many girls and probably has been cheated on by lots of girls and just can not stop getting hurt. So the boy stops dating and because he wants fucking love but not a relationship cause he is scared of getting hurt, he turns into a Fuck boy. Which then he hurts girls by teasing them on thinking he likes them but doesn't and just wants to fuck or cuddle.
Jessy: Josh is such a fuck boy!
Alyssa: No hese not, hese just been hurt by many girls and have given up on dating