Shermie's taller, older, and more muscular. In terms of actual volume, Mai's are probably the same size, with room to grow.
kind of like that, it follows martial arts logic; the taller the charcter teh higher the bust measurement is, because of proportions; then the characters who do grapple, like shermie, mary or vice have a wider back. cup size you are correct regarding mai, she is as big or bigger than most.
