Akira is convicted of a crime a year before high school, being moved to Tokyo in the same year to attend a school that would accept him. With it not being Shujin. No one finds out about his record, but he's determined to bury it six feet under with a new identity. He builds his reputation in his first year of high school not as a Detective, but as a budding youth activist with Toranosuke Yoshida as his mentor.
His charisma is what skyrockets him to being a common name around Tokyo's streets, where he's often seen outside of the station with Yoshida or alone. He advocates for reform, but doesn't believe that the Phantom Thieves are doing anything but being a temporary mend to a root illness. People are willing to listen and he makes good points to the public about how reform needs to come from themselves, not from the Phantom Thieves.
Akira’s power comes from Yaldaoboth, who gives him this power and in his eyes, it’s a chance to get back at Shido in some way. Akira knows that no matter what happens, his record stays and he's bitter about it. He's especially bitter towards Shido, who got him convicted in the first place. With Yoshida’s help, he’s able to find some leverage to work as an intern for Shido. With his social prowess, Shido sees something in him that reminds him of himself and keeps him at his side.