how did the artist not notice that
Hahaha, speaking from experience it's easier than you think. Although upon further consideration this may be more of a case of bad proportion/angles than a backwards foot; this artist struggles with that here and there.
as an artist, mistakes are common in anatomy, its not easy to capture the shapes
Or when Riko throws Momo back on the bed, she has these huge thighs and skinny calves — like chicken legs ┑(￣Д ￣)┍
Lulz. It's so hard for me to take it seriously when major anatomical art goofs happen. Riko's foot in the last panel of ch 29 is on the wrong leg. XD