Ako Izumi is student number five in class and plays in the band "Dekopin Rocket." Although she doesn't see herself as special, she is one of the more well-behaved students (compared to others). She works as an assistant nurse at her school despite hating blood. Ako is shy, athletic, and leads a soccer team. While not particularly interested in Negi like most girls, she is cheerful and helpful nonetheless. Despite having low self-confidence due to a scar on her back that she believes makes her unattractive, Ako tries to keep it hidden from others.
After being accidentally transported to the Magic World, she is forced to become an indentured servant along with Akira and Natsumi to pay for medication she received. After Negi, disguised as "Nagi" using "Age Deceiving Candy," helps her overcome her scar somewhat, she develops a crush on him, believing him to be Negis cousin.
She eventually makes a pactio with Negi, just before the trip to Old Ostia. The story behind the scar on her back or her phobia of blood is never revealed.
She eventually finds out that Nagi is actually Negi (who did not understand the real implications of the deception), which leaves her heartbroken, until she confesses her love for the nonexistent Nagi, asking him to fight Rakan for her sake.