|“||An alien. He took her with him back to space.||”|
Akio appears to have a laid back and casual personality. He does not seem very concerned with rules, often skipping school and smoking. He is also a "player", getting into relationships with multiple girls without their knowledge. Despite entering so many romantic relationships, the only person he ever fell in love with was Naoko, although he himself didn't admit to this until after her death. Akio never minded the fact that Naoko was in love with someone else, and loved to spend time with her. According to him, Naoko was at her most beautiful point when she didn't try to put on a cheerful mask, and let her real self show. After Naoko's disappearance, he seemingly moved on with his life, but never actually stopped loving her, so much so that when he recieved a letter stating that Naoko was dead two years later, he instantly decided to visit his old highschool, where he met up with Touka Miyashita, who advised him to get over his old soulmate.
Akio is a young man with longish brown hair and brown eyes. He is shown wearing the Shinyo Academy male school unifrom.
Akio was a normal student at Shinyo Academy. By chance, one day, when smoking a cigarette behind the school, he witnessed two fellow students, Naoko Kamikishiro and Shirou Tanaka. Naoko tried to confess to Shirou, but he ran away, without leaving her a chance to say anything. Left behind, Naoko called out to the hiding Akio, having noticed him from the start, and asked for a cigarette for herself. From then on, the two started going out, and, soon, Naoko managed to convince the hesitant Shirou to become her boyfriend.
Boogiepop and Others
Chapter Two: The Return of the Fire Witch
Somebody brings up the rumor of Boogiepop in class, and Kazuko Suema, unfamiliar with the urban legend, asks about it, and they fill her in. Upon learning, Kazuko internally scoffs at the legend, thinking it to be absurd and stupid. Once Akio Kimura, the class lady killer, walks in, the girls immediately end their conversation, Kazuko concluding that this urban legend is being kept secret from boys.
Chapter Four: I Wish You Heaven
Two years after graduating high school, Akio Kimura receives an anonymous letter telling him that Naoko Kamikishiro is dead and that he should forget about her. At first, he suspects the letter to be a prank, but he thinks that it's strange for a prank to arrive after so much time passed. Akio then remembers the strange way in which he and Naoko began a relationship.
While out smoking a cigarette behind the school, Akio overhears Naoko confessing to a younger boy named Shirou Tanaka, who suspects Naoko of tricking him, due to the unusual nature of a third year student asking a first year one out. As Shirou waits for Naoko to say what she had to say, he eventually shrieks that he "can't do this" and runs away, leaving a disappointed Naoko behind. Then, she turns toward Akio (whom she'd noticed since the beginning), and joins him for a smoke. Akio, noticing the tear tracks on her face, concludes that she was serious about her confession. Akio tries to console her, but Naoko tells him not to be nice to her, or else she may fall for him as well. Then, the two skip class to continue hanging out. After this, the two make it a habit to go on various dates.
Eventually, Naoko manages to convince Shirou to go out with her as well, with Akio often commenting that he doesn't know what she sees in the boy. While on a ferris wheel at an amusement park, Naoko and Akio discuss Shirou, with Naoko expressing her reason for liking him, and the first time she saw him at an archery competition, predicting that he is meant for bigger things. Then she says that she prefers playing around with Akio because he's a mess, just like her, saying that Shirou doesn't understand her at all. Then, Naoko leans in to kiss Akio. Upon being asked whether he does that with Shirou too, she bluntly denies the claim. Akio then thinks that she finds her most attractive when she's being herself, not deliberately trying to act cute or appealing.
Returning to the present, Akio still has that letter on his mind, and decides to skip his university classes and visit the town where he attended high school, where he enoounters Touka Miyashita, a former classmate, who failed exams and had to repeat a year. The two catch up, talking about Touka's boyfriend and Akio's college life. The conversation soon turns to Naoko, whom Akio still hadn't moved on from. Touka, noticing this, becomes irritated and drags Akio to the cafe Tristan, where she scolds Akio for playing a hero in the past, when he took the fall once the school discovered signs of Naoko having invited a stranger to live in the school, leading to his suspension and a scandal among the student body, with his reputation permanently ruined. He then tells Touka that he did actually know who Naoko was seeing, namely, an alien, who took her back to space. Upon hearing this answer, Touka slaps Akio, telling him to move on already, although his words were exactly what she'd told him once.
One day, Naoko asks Akio if he thinks that human existence is justified, to which Akio responds that he doesn't think so. Then, Naoko tells him about how she met a man from outer space, and how he was sent to Earth by some large consciousness. She explains that he tried to mimick a human, but didn't get it exactly right, and ended up over-evolved, which put him under some corporation's attention, who cloned him, and ended up making a man-eating monster, who escaped from the research facility. Therefore, Echoes went after it, to try and stop it from taking over the world with its abilities. Upon hearing this, Akio asks why Echoes would care about what happens to the human race, and Naoko responds that he's just nice. When Akio asks where Echoes is now, Naoko says he's at the school, and makes Akio promise that he won't tell anyone (a promise which he keeps, leading to his suspension). While still not sure what Naoko's story about Echoes means, Akio tells her that if she just opens up her heart to him, he'll definitely learn to like humanity. Then, the two part ways. That was the last time Akio ever saw Naoko.
When their orders arrive, Touka notices the waitress' look of interest, and cools down, apologizing for slapping him. She then tells Akio that Naoko would have probably wanted him to move on too. Then, as the two part ways, Akio tells her that she should try to keep her hero complex under control and study. As he turns to leave, she calls out to him again. However, it seems to him like a boy took her place, like she transformed. Boogiepop, having momentarily taken over Touka, tells Akio that Naoko performed her duty admirably, and that the only thing he can do is perform his as well and make her proud. Then, the shinigami disappears into the crowd, leaving Akio to stare after her, speechless.
Akio arrives at Shinyo Academy, sneaking in through a gap within the fence that Naoko had shown him years earlier. Even though he knows that the sender of the letter would not be here, he can't help but show up, as it is the only remaining place that connects Akio to Naoko. As Akio wanders through the school, he thinks about his experience with Naoko, about how she told him and only him about her secrets, and about how he'll continue to love her for the rest of his life, impossible to understand as she was. He then arrives at the gym storage room that Naoko had hidden Echoes in. As he looks around with a flashlight, he discovers a cover near the main entrance, leading to the foundations of the gym, designed to absorb the impact of an earthquake. When he turns to exit, he notices something on the floor. Examining it closer, he realizes, to his horror, that it's a mummified human hand. Soon after, the hand crumbled into dust, perhaps due to exposure to the air outside. Akio wonders what could have happened two years ago, but there's nobody there to give him any answers.
Akio and an unknown other person are shown conversing about Notorious I.C.E.. Akio asks what I.C.E. means, and the other person explains that it is a designation for failed synthetic humans. Akio argues back that Notorious I.C.E. has incredible destructive power, even being called a Super Build. The other person agrees, speculating that he may have some hidden ability, then remembering and bringing up the incident that Notorious I.C.E. was involved in while living in Akio's country.
- Akio's last name, Kimura, is written with the characters for "tree" and "village".
- Akio's first name is written with the characters for "light" and "masculine".
- Akio is the only character from the first novel to not be featured at all in the anime adaptation.