Volume 4 - Fall of the Scarlet Ammo

Fall of the Scarlet Ammo is the fourth volume of the Hidan no Aria novel series released on August 25, 2009. This volume begins the IU arc.

Chapters

 * 1st Ammo - Invisible Bullet
 * 2nd Ammo - Emergency Mission -Quest Boost-
 * 3rd Ammo - Summer Festival
 * 4th Ammo - Infighting -Falling Out-
 * 5th Ammo - Golden Pavillion -Abu Simbel-
 * Last Ammo - Awakening of the Scarlet Ammo
 * Epilogue - Go For the Next!!

Trivia

 * The volume is released exactly one year from the release of Volume 1.
 * The first volume to feature a male character on the cover.