Y'know, a lot gymnasts, ballerinas and the like could fall into the butterfaces category. Not all of them have huge tits and nice asses, but they'll still have pretty nice skinny bodies. Flat tummies, nice legs, etc.
Yeah Michelle might not be GORGEOUS, but her body's not that incredible either so it balances out. Just a regular cute girl. There has to be a certain gap between the quality of body and the quality of the girl's face to be considered a butterface. She's like a 7 face and a 7 body so it's about right. Butterfaces are 10 bodies with 4-6 faces