Cassino, what is sexy to ya?
Sexy is as sexy does, Mama. /Forrest Gump.
There can be sexiness in just about any girl, I think. I'm personally a fan of the stomach/hip/backside/upper thigh area as a whole.
But in general, work with what ya got.
EDIT: And Josh, of course.

EDIT2: Cleavage is nice. But it's a tease. Eventually, I'mma need to see the twins.