Ako Izumi holds student number 5 in Mahora Academy's class 3-A. She possesses light blue hair, red or amber eyes, and stands 148 cm tall with measurements of B75-W54-H76. Born on November 21, 1988, she is a Scorpio with blood type A. Despite a significant fear of blood, she works as an assistant in the school nurse's office. This fear connects to a large scar on her back, which fuels deep insecurity and a belief it makes her ugly and unwanted, compelling her to constantly conceal it. This contributes to her shy personality and low self-confidence, often viewing herself as a supporting character rather than a protagonist. Her daily responsibilities include managing the boys' middle school soccer club and overseeing class 3-A's sanitation duties. Athletic yet reserved, she maintains a well-behaved demeanor. She shares close friendships with roommate Makie Sasaki, Yuna Akashi, and Akira Ookouchi. Ako also plays bass guitar in the band Dekopin Rocket alongside Misa Kakizaki, Madoka Kugimiya, and Sakurako Shiina. During the Mahora Festival, Ako develops strong feelings for Negi Springfield disguised as his older form "Nagi." Her infatuation leads her to invite him to festival activities and participate in a date, placing second together in the Mahora Best Couple Contest. Nagi encourages her to see herself as a main character, boosting her confidence. She attempts to confess twice but falters, first asking if he likes Japanese squid and later requesting his email address during a concert. Believing Nagi returned to England after the festival, she sends him pictures in various outfits, including a bunny-girl costume at Misa's instigation. In the Magic World arc, Ako accompanies Negi's group but falls severely ill after Fate's attack separates them. The costly medicine (1,000,000 Drachma) forces Akira and Natsumi to sell themselves and Ako into slavery to afford it. After Negi rescues them, she protects his secret identity by offering to sacrifice her freedom to Tosaka, who returns the evidence without enforcing the exchange. Ako becomes the second person to confess directly to Negi. She later initiates a Pactio contract specifically with his true ten-year-old form. Her Pactio artifact, "Cultrix Cum Traumate," manifests as a large syringe named Mysterious Syringe. Injecting it into a target (reportedly requiring rectal administration) provides a magical boost; it can also inject poisons that reverse senses and direction. Alternate media depict variations: a catgirl nurse outfit with a syringe (*Negima!*), a first-aid kit with healing bandages (*Negima!?* cosplay form), and a winged blue nurse outfit riding a syringe (armor form). Her character resolves with the scar magically healed during the final battle against the Mage of the Beginning. After graduating high school, Ako studies healing in the Magic World, returning as a first-grade healing practitioner. She works as a nurse alongside Akira Ookouchi and continues her studies under Konoka Konoe's mentorship.