Aiko Senoo is a main character of the Ojamajo Doremi 16 Light Novels.
When highschool starts she shocked her friends with an abrupt return to Misora.
In 10th grade, Aiko joins Doremi at Misora Prefectural High, revealing that her mom got a job at a brand new retirement home opening up. Since then she has been working hard to achieve her dream of some day joining the olympics as a track runner. She has been pretty busy as a result and has already set records and won achievements.
Aiko is a tall, tanned girl with big, dark blue eyes. Her hair has started to grow out, with the end portion still flipping just slightly on the ends. Her split-curls are still there, as is a very small amount of forelock and bangs. However, her forehead is still very exposed.
In one image, she was depicted in a white and dark blue school uniform - most likely the outfit worn before she transferred back. Her casual attire in the first book was a loose, opened jacket with a shirt, a pair of shorts, tube socks, and sneakers.
Aiko is a tomboy with a lot of energy and spirit. Her temper (while already pretty rare) has toned down even further, although she tends to bicker over sports with people, especially if they deface or critisize her favorite sports team, the Tigers.
It was revealed early on in the Manga that she was dating her childhood friend, Anrima for a while. It is currently unknown if she talks to him currently, as she pointed out that she broke up with him in seventh grade when he made a marriage-related joke that severly offended her.