Hi and thank you so much for this query. I am so sorry to hear about the chubby cheeks you have reported. This is unusual that you would have excess fat build up only in your cheeks. The problem here is that you do not like the way it looks and how your face looks and not the underlying chubby nature. This is more of a body dysmorphic disorder where the concern is not at ease with his/her body s morphology. My advice to you is to look for ways to be at peace with your body. If you cannot, talk to a psychiatrist for help. There is no way to selectively reduce the size of your cheeks. Sports or exercise would not selectively do this given your skinny nature. I hope this helps. I wish you well. Feel free to ask more questions and request for more information if you feel so.