Skinny vs, Muscular back?

So I am aware that the back of a woman doesn't count as much as bum, boobs or legs but still it somehow affects the overall shape of the female body. So skinny or fit back?

examples:
Skinny
2.bp.blogspot.com/.../714157-0115_2.jpg

Fit
https://x5fitnesscamp.com/images/back-2.jpg
Skinny
Fit
Select gender and age to cast your vote:
Skinny vs, Muscular back?
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