Ya'll seem to like Billie.
So here's some more details on her concept and design if you'd like
Billie isn't exactly a new character from me, but she has gone through a couple iterations. The one at the top is close to the current design but the legs there are a little too "sleek" or catlike. But at least you can see how she's supposed to carry her cannon. Most of the centaur's torso is a battery for charging the accelerators in the mass driver, allowing her to punch holes in the biggest mecha. She can also serve as a portable battery bank for the ranger crew and their equipment!
Billie's human body doesn't have legs, due to a birth defect caused in part by the radiation in their post apocalyptic wasteland world. She was able to get different prosthetics and adapted well to different frames from wheelchairs to legs. I still haven't decided how much of her body is mechanical but I think it's just her legs as the most recent drawing shows.
An earlier idea was for her to be a small woman in a large exoskeleton centaur frame however I went ahead and gave her big muscles because that seemed much more fun. And I'm pretty sure it's gonna stay that way from now on.
She is one of a few rangers as part of the crew of The Big Bug, a large land ship that goes across the wasteland. They move from settlement to settlement, providing medical and mechanical aid when they arrive and act as a supply lifeline between different communities. The rangers explore and scavenge parts from the wasteland, and are equipped to deal with hostile wild mecha.
To get around on the ship, Billie will separate from her hind legs. Sometimes she's even seen with much smaller front legs or her wheelchair, depending on which one's more comfortable for her on different parts of the ship.