Responses
could just be the manga mentality of 'chubby people are short'. I haven't really ever seen a fat person that was tall in manga unless they were made to be imposing, usually if it's to show ugliness they're short and fat.
I guess it's easier to emphasize their weight if they're short
So I get that if Hyunsuk lost weight he would look closer to his fake body, but what about the height? He is unusually short, unless he gets a spontaneous growthspurt since he's still in high school