Sayo Aisaka is a character from the Mahou Sensei Negima anime and manga.
Sayo is the 1st student in Japanese alphabetical order of class 2/3-A, she is the hapless and meek ghost of a former student, occasionally accompanied by a pair of hitodama. More often frightened than frightening, she is invisible to virtually everyone, and her presence goes mostly unnoticed (though Professor Takahata had her included in Negi's class registry, with a note not to change her seat). Eventually, she does get noticed by her teacher Negi Springfield and most of her classmates and becomes a friend and ally in his quest.
In the AWA fics, Sayo is a student at the AWA Academy.
Sayo's appearance consists of white hair and red eyes, gives her the impression of an albino, which looks appropriately creepy for a ghost. Similarly, Sayo was designed in wearing an old-fashion "sailor-fuku" style school uniform as contrast to the other students in the school who all wear preppier uniform clothing and to show that she lived and died in another era. She is also depicted to have no feet (being a ghost). In both anime series, however, she is depicted to have feet (although an eyecatch of her in the Spring OVA shows her without feet). As a further comparison, however, Sayo is depicted as a walking ghost in the first anime, while she is sometimes seen in Negima!? floating in midair. In fact, in the first series, she falls to the ground while trying to catch a butterfly flying high.
It should also be noted that Sayo, being a ghost, has been wearing the same uniform regardless of the change of seasons. In case of the manga, she is constantly seen in her black winter uniform with white collar and red ribbon. In the first anime series, as to be noted below, she is wearing a white summer uniform with blue-collared white blouse, blue skirt, and green ribbon.
She has low self-esteem and is not skilled at being a ghost, tripping despite the fact that she doesn't have feet and being completely unable to (intentionally) scare people. Sayo has been friendless and lonely for around 60 years since her death, which made her very desperate for a friend. Her attempts of making friends has led to misunderstandings, which are discussed at the following section. After her discovery, she does gain friendship and understanding from her teacher and her classmates. Her originally morose personality has become happier and more outgoing.
Sayo is kind and tries to see the world on the bright side. She really loves her family, especially her sister. She is very sensitive to Tsuwabuki which connects to her former human life
- Ghost Powers: Sayo has all the standard powers of a ghost, though she is not very experienced in using them, despite having them for over 60 years. These abilities include floating/flying, intangibility, invisibility, (though this was due to no one noticing her in the first place), possession of other people, levitation of objects, and other skills commonly associated with poltergeists. However, Sayo also shares the same weaknesses of ghosts and is vulnerable to spirit wards, magical spells, and weapons (such as Mana's spell-breaker bullets and perhaps any 'ghostbusting' equipment created by Satomi and Chao).
- Ghostly Stealth: Sayo typically isn't noticed when not physically manifesting or controlling a fetter, even by spiritually aware persons such as Mana or Setsuna. Only Zazie and Eva initially seem to be able to see her. This stealth later allows her to work around the limitations of Kazumi's artifact.
- Sayo Doll: Since she is bound to the grounds of Mahora Academy, Sayo can only leave the area by means of a mystical doll given to her by Kazumi. By possessing the doll, she is able to interact more physically with the living world and can even use her ghost abilities outside of the doll. She uses the doll as an anchor point, and so long as she doesn't stray too far from it, she can exist in places outside of the academy. This has the additional benefit of being small enough to ride on one of Kazumi's camera golems (it has a seat and writing on it indicating it is for her use).
- Pencil/Pen Twirling: Though not an especially useful skill, Sayo is a master of spinning pencils and pens about her fingers and hands. It is presumed she learned the skill to offset the boredom during the summer vacations, when there are no classes. This skill is demonstrated in volume 19, chapter 175, A Single Frame of a Youthful Summer, on one page titled: “Spinning for 60 Years.” The same chapter also shows Sayo's "friendship" with Zazie Rainyday.
- Sayo Robot: In volume 28, in order to possibly make a pactio with Negi, Sayo is given a robot made by Haruna, that looks identical to her full sized body, with feet. She controls it not by possession, but by a cockpit in the torso where her Sayo doll sits. Upon seeing the amazing combat capabilities of said robot, she promptly forgets anything about forming a pactio.
- Gatling Gunner Skill: While there was no indication of this beforehand, she shows a great deal of proficiency when controlling the gatling gun of the Great Paru-sama.
- The land-locked spirit of the Mahora Junior High 3A classroom's first row window-side seat, but actually she can go to places that are near to the school
- Died at the tender age of 15, she had been in Mahora for over 60 years
- One heck of a scaredy-cat, she can't stand staying at the classroom alone at night so she would go to the convenient stores or family restaurants
- Her seat was known as the "Non-sit-able Seat" because everyone said you'll feel a sudden chill when you sit there
- Since her sense of existence was rather weak, even most exterminator (e.g. Setsuna) and people with spiritual power (e.g. Mana) could not notice her
- Currently in 3A, those who can see her included: Negi, Asakura (whose seat was next to hers) and the vampire Evangeline. This has changed during her time in the magical world when all of Ala Alba could see her.
- She can cause poltergeist phenomenon and create words of blood on the walls if she really tries.