Chester's just another member of the tennis team and a fellow classmate at CrestHaven university. He can be hot-tempered at times, but you can count of him to help keep you motivated to improve yourself. As much as he likes to work out and try to make himself more muscled than he already if, but he enjoys his food a bit too much to get rid of that gut.
This image might get reworked in the future to better suit the style of the other characters too.