Keita Aono is the main human protagonist of Betterman, whose point of view most of the story is seen from. Keita is a seventeen-year-old high school student who, through a chance reunion with his childhood friend Hinoki Sai, finds himself recruited as a Head Diver for Akamatsu Industries. He is quite different from the typical mecha pilot seen in most anime, being rather awkward and prone to panicking easily. However, on multiple occasions, he shows his willingness to place himself in danger to protect those he cares about. He has especially high readings as a Dual Kind, and at one point is even able to pilot a Neuronoid by himself. This is a result of a transplant of dura mater he received as an infant, due to a serious head injury, from a woman named Laurier Noir. Although he shows an attraction to several girls throughout the series, he is especially fond of Hinoki, and makes no secret of his desire to pursue a relationship with her, despite the rather apathetic attitude she often displays towards him. Keita is voiced by Kappei Yamaguchi.