("Kin no Kutsu, Gin no Kutsu", "Golden Shoe, Silver Shoe(s)")
One of the original series by artist Kouno.
A story about a girl with a "Golden Shoe" (a golden prosthetic right leg) and a male android called "Silver Shoe(s)" in a post-apocalyptic world.
It's in the same world as Masao's other series Ishida to Asakura, though at some point in the future.