K, sorry that was fault on my part. ^^
Anyways, in more detail what I said was as follows,
Buu essentially doesn't have any muscle tone at all. He is morbidly obese, so if you live in America you can go to the nearest McDonalds and check out some ppl eating there. See if the average person has any muscle definition at all in their arms. Chances are because they are overweight, no they don't. The fat covers any definition they have so it won't show. So the tricep and shoulder definition you have should vanish. It's fine if you want to add wrinkles or what not between his bicep and forearm where it bends (that area does tend to be exaggerated in overweight people) feel free. But other than that, his arms look very healthy when it just isn't the case.
And for the soot in the face remark, you used a pink base color, which is obvious choice for Buu. However, in the attempt to provide any definition it looks like you just stuck to a burn tool (highlight i'm guessing) so there really isn't any color variation at all and it comes out looking very dull. I used soot as an analogy because the blackness of the shading without color variation is kind of what soot would produce taking away any shine. (Buu is a very shiney character BTW, so white highlights are a very good way to go)
If you need any more clarification lemme know. ^^
Can't wait to see how this turns out.