What is Shadow Caster?
1.
An erect (usually female) nipple that protrudes through clothing enough to cast a shadow in full light.
Dude, check out the shadow casters on that chick's fun bags!
See
2.
A pest, a nuisance, someone who follows you around constantly, but poses no danger like a stalker.
That guy is such a shadow caster. Every time I turn around, there he is...all up in my face.
