It's by fairly well known superwoman artist Femfortefan and based on a story of the same name that I wrote a while back. He draws girls with more muscle than I normally like but he's a bit more toned down here and I think it came out well.
If you like watching a girl become stronger than Superman, you might enjoy it!
Contains some explicit material
Page 1 starts here:
steelknight3000.deviantart.com/gallery/#/d4zj6zd 
