The eyes in the top/left panel are way off... I think the shading of his trousers in that panel isn't right also.
You're also using too many straight lines in my opinion. i.e. the moobs in the top/left, the belly in the top/right, the outlines of his head, his shoulders, his arms.
His back also is odd. The line goes way too high up.
Then the flat light skin color seeems a little wrong (the one you use at his shoulders in the top left panel).... You could make it more orange...
Then there is that issue of banding. Examples are his belly (black/brown/orange), his lower legs, his feet. (the outsides to be exact).
His anatomy seems strange but I have little knowledge about that myself.