Dr. Robotnik is an obese human with exaggerated proportions. He is known to sometimes wear a onesie at home.

Overall, Egbutt is a big smelly jerk. That's the nicest way of putting it. It is a fact there isn't any kindness inside of his tiny, rotten, greasy black rock heart. But he still has a heart! Just a very scummy one. Unlovable and rotten.