Aria the Scarlet Ammo (Hidan no Aria) 1 (MF Bunko J) [Light Novel]

[Machine Translation] Tokyo Butei High School is a special school that trains detectives who use military force, known as "Butei". Kinji Toyama is a second-year high school student in the detective department, who has a constitution that activates his brain with a "certain trigger," and he spends his days seeking peace and tranquility while keeping this secret from everyone around him. However, on his way to school, he gets caught up in a bombing incident and meets Kanzaki H. Aria, a super-elite member of the Assault Department, and his daily life changes into something far from peaceful. Aria, the strongest S-ranked military detective, and Kinji, a (usually) ordinary person, face off against thugs in this large-scale action and romantic comedy.

東京武偵高校、そこは武力を行使する探偵―通称『武偵』を育成する特殊な学校。「あるきっかけ」で頭脳が活性化するという体質を持つ遠山キンジは、そのことを周囲に秘密にしつつ、平穏を求めて日々を送る探偵科所属の高校二年生。しかし、通学途中に爆弾事件に巻き込まれ、強襲科の超エリートである神崎・H・アリアと出会ってしまったことにより、キンジの日常は平穏とは程遠いものへと変わっていくのだった―。Sランクの最強武偵・アリアと、(普段は)ただの一般人・キンジの凸凹コンビが凶悪犯に立ち向かう、大スケールアクション&ラブコメディー。