Yea I was about to say, little to no breasts would help define her pecs as well, but it all really depends on how she works out and what her diet is like, cuz not all muscular ppl have really defined muscles! I'm a real fan of the whole "muscle gut" look.
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Dendropsyche
She's adorable! I love her broad shoulders. If you want to make her really muscular, some thick traps should help define that :3