When I rotate my legs using the assigned bone, it weirdly makes the legs thiner, any solutions? For some reason when I rotate part of an object it makes the legs thiner

Without rotation



With rotation



Anyone know how to fix this issue?
I have parented the object to the bones with empty groups
It's because the topology of your legs doesn't have enough geometry, so it doesn't deform well.

Look at some examples comparing good and bad joint topology. (The good ones have a denser, "capped" extrusion)