Volume 1 - Aria the Scarlet Ammo

Aria the Scarlet Ammo is the first volume of the Hidan no Aria novel series released on August 25, 2008. The novel is the beginning of the series containing the start of the prologue section of the story with the IU storyline. This volume contains the Introductory and Butei Killer arcs.

Summary
Tokyo Butei High School, a special school where armed detectives, also known as "Butei", receive education as well as training. Kinji Tohyama, an Rank E sophomore, who is trying to leave the life of a Butei due to a recent tragedy, has an unique body that can initiate an ability called "Hysteria Mode" when it is stimulated in a certain way, which he tries to keep it a secret. However, all his dreams of living a normal life gets shattered when he becomes a victim of a bombing incident and meets Butei High "Assault" department elite, Aria H. Kanzaki.

Chapters

 * Locked and Loaded
 * First Bullet: La Bambina dal'ARIA
 * Second Bullet: Aria H. Kanzaki
 * Third Bullet: Assault Division
 * Fourth Bullet: Under the Bangs
 * Fifth Bullet: Olmes
 * Final Bullet: La Bambina dal'ARIA...
 * Epilogue: Go For the NEXT!!!

Plot
Sophomore at Tokyo Butei High School Kinji Tohyama wakes up to the sound of his doorbell ringing. Despite it being so early, he drags himself out of bed and opens the door revealing the ringer was fellow student Shirayuki Hotogi. Following a brief conversation, Kinji lets her in and she serves him breakfast. Upon finishing, he changes into his uniform and Shirayuki takes her leave while Kinji continues to laze about. He notices the time and rushes out as he's soon to miss the 7:58 bus from his dorm.

Kinji did end up missing the bus so he was forced to take his bike instead. As he arrives to school, a remote controlled segway toting an uzi pulls up and warns him should he slow down or use his phone the bomb underneath his seat with detonate. Kinji speeds into an empty sector of the school to avoid any collateral damage should the bomb go off however he notices a pink haired girl with twin tails standing on top of the 7th story of the girl's dorm. To his surprise she jumps off and open a para-glider, steering towards him. Kinji called out for her to get away but she ignored his calls and fired at the segway destroying it. She came back around and managed to grab his off the rigged bicycle. The explosion knocks the para-glider forward and they crash into a nearby storage complex rendering both of them unconscious.

Kinji wakes up first inside of a jumping box and, to his surprise and panic, the girl who saved him is right on top of him. From a name tag within her uniform, she learns her name is Aria H. Kanzaki. However, Aria wakes up and notices the embarrassing situation and takes out her anger on Kinji. As Kinji tries to reason with her, more segways pull up and open fire on the box. Aria immediately snapped into action and fired back, not noticing her chest pressed directly into Kinji's face. Unable to hold it back this time, Kinji enters Hysteria Mode as the segways temporarily retreat. Now in a state of hysteria, Kinji calmly carries Aria out of the box and charms her into sitting still while he deals with the segways. In a quick motion, he dodges the first volley of their shots then fires back - each bullet expertly goes down the Uzi's barrel, destroying it. Kinji returned to a still flustered Aria and, after calling her a middle school student, sent her anger over the edge. She fired at Kinji until she ran out of ammo. Taking the chance, Kinji lunged at her to disarm her, but she quickly turned it around and slammed him in the ground. Aria attempted to reload but Kinji had snatched her spare magazines during the flip. She then switched to her twin Kodachi and lunged for him but slipped on the bullets Kinji had scattered again. She tried to compose herself, only to slip and fall again. Kinji took this opportunity to flee as Aria called out threatening him.

Kinji laments what had happened the previous morning as he returns to class as he was fully aware of what he was doing. He arrives, late, to his class and much to his horror Aria was a new transfer for his class and requested to sit next to him. Despite Kinji's visible distraught, his friend Gouki Mutou gave up his seat next to Kinji so Aria could sit next to him. So Aria took her seat next to Kinji and returned his belt, giving the wrong impression to the entire class. Riko Mine only made the situation worse by working up the class by bringing up the idea he and Aria were dating and "did it" because he didn't have his belt. This did not sit well with Aria, however, and she opened fire in the class room to silence everyone. Everyone fell silent from fear and she made it very clear that she and Kinji were not lovers.

Trivia

 * La Bambina is Italian for the child.