Choo-Choo Bear from Something Positive

It's Choo-Choo-Bear from the online comic, Something Positive. CCB is very old, has a weird bone disease, is hairless, and has had so much chemotherapy that he is practically boneless! But that doesn't stop him at all--no way! He eats like an amoeba and can shift his shape with little effort. He's also got a bit of an attitude problem, but don't mention that around him or he'll engulf you. The background contains the 'words' he frequently says. That yellow face in the corner is the logo for the comic.