Kumi Sugimoto holds the position of second assistant manager for Nankatsu Middle School's football club during the Boys' Fight arc. As a first-year student, she is younger than most third-year team members. Her personality radiates energy, cheerfulness, and occasional naivete, consistently showcasing straightforward actions and an unwavering plucky optimism. Physically, she sports brown or dark brown hair, initially worn in two shorter ponytails compared to Yukari Ishizaki. By the Battle of World Youth saga, she cuts her hair short after the Asian preliminaries, tying this change to a fortune-telling ritual. In the 2018 anime, her design features light brown hair, caramel-brown eyes, long face-framing locks, and large, shiny eyes that accentuate an innocent, cute appearance. Her background includes a close friendship with fellow manager Sanae Nakazawa, sharing romantic feelings for team captain Tsubasa Ozora. Kumi confesses to Tsubasa before Sanae, but he gently declines, revealing his love for Sanae. Kumi responds maturely, stating she anticipated this outcome and emphasizing how confessing resolved her uncertainties. She then urges Tsubasa to confess to Sanae promptly, aware of rival Koshi Kanda’s interest, and transitions into supporting their relationship. Beyond middle school, Kumi supports Nankatsu High School and the All Japan Youth team, frequently attending national matches alongside her fortune-telling grandmother. She exhibits sensitivity to predicting match events, though Yukari advises her toward greater positivity after the Japan Youth versus Sweden quarter-final. Her commitment lasts until the "Golden Generation" completes high school. Kumi's name combines "long time" (久) and "beautiful" (美) for her given name, while her surname Sugimoto means "cedar" (杉) and "base/origin" (本). Non-Japanese adaptations rename her Eva Toscano in Latin America and Susy (or Suzie) Spencer in Europe. Her character evolves from Tsubasa-centric motivations to genuinely caring for football and teammates as older siblings, demonstrating unexpected maturity in handling unrequited feelings. She appears across manga arcs including Boys' Fight, J Boys' Challenge, Battle of World Youth, and the Holland Youth special, but is absent from the Road to 2002 anime and Rise of New Champions game.