Sumiko is a sporty girl who is training hard to be a career athlete. She's extremely serious about eating healthy and getting lots of exercise. Known to go to great lengths to attempt to convince others to adopt her own lifestyle choices.

"Ryoba! On your feet, senpai! Let's train!" Sumiko yelled excitedly at her crush, Ryoba Aishi, as they were about to run track since Sumiko Is very athletically flexible.