Кінухата Сайай

She is a member of ITEM, led by Mugino Shizuri. She later becomes its leader in Volume 19, after Shizuri's defeat in Volume 15 at the hands of Shiage Hamazura. Despite being a powerful Psychic, Saiai is one of the most mellowed-out characters in the group; she isn't a screw-up like Frenda, nor is she as frightful as her leader, Mugino. She enjoys bad movies and likes to tease others, Shiage in particular because of his reaction to anything sexually suggestive. She also likes to add "super" (超, chou) to her remarks.

Her ability is the Level 4 Offense Armor (窒素装甲, Chisso Soukō?, lit. "Nitrogen Armor"), which she uses to control the nitrogen in the atmosphere to create a few centimeters of solidified nitrogen to act as a barrier. She can use this to attack and defend. Like Accelerator's AIM vector shield, the primary function of her ability is to create an armor of super-compressed nitrogen around her, she fights a sniper in volume 15 and Academy city's special sniper rifle is shown to have no effect on her other than to knock her backwards a little. Because of her ability, she carries around a small amount of nitrogen for use at all times.

According to Teitoku Kakine, Saiai is a leftover from 'Project Mayday of Darkness' (usually referred to as the "Dark May Project") whose aim was to create a personal version of Accelerator's ability by using a similar pattern of ability operation. This was done by referencing the cognitive patterns of Accelerator himself in order to optimize the personal realities of certain espers taking part in the experiment. Though the details are not mentioned, Saiai only succeeded in creating an automatic self-defense capability that activates if she is attacked.