Black★Rock Shooter: Innocent Soul

Black★Rock Shooter: Innocent Soul (ブラック★ロックシューター イノセントソウル, Burakku Rokku Shūtā Inosento Souru) is an action-fantasy manga series by Sanami Suzuki. It was serialized on Kadokawa Shoten's Young Ace magazine between June 2011 and May 2012 for a total of 12 chapters. Its chapters have been compiled into three volumes, which were published in paperback as well as electronic formats.

The story follows a girl in the "Threshold" (狭間, Hazama), a world between Heaven and Earth. Stagnant souls — those that could not ascend to Heaven with the weight of their own burdens — have drifted to this world of constant warfare.

Plot
Innocent Soul follows the solitary journeys of Rock, a Black Star — one who is tasked with the duty of purifying the souls, giving way to their ascension to Heaven. In her journeys, she is joined by Ron, who also becomes her weapons when faced with the need to defend themselves. During their journeys in the vast world of the Threshold, they would meet stagnant souls of different personalities and burdens in life, and she would sometimes meet other Black Stars as well. As the story progresses, Rock would rediscover her true self that has been lost upon becoming a Black Star.

Characters

 * Rock (ろっく, Rokku) - A girl with long black hair in twintails and a flame in her left eye. She wears a peach-colored striped dress, thigh-high boots, and a black poncho. Her duty is to cleanse the souls of people who wander in the Threshold.
 * Ron (ロン, Ron) - Rock's constant companion who comes in the form of a snake-like creature most of the time. When needed, it transforms into Rock's primary weapons: a hiltless katana and a cannon.
 * Dead (デッド, Deddo) - A girl with two black skeletal horns, wearing a sleeveless top. She wields a fancy three pronged sword and rather than releasing souls after she captures them, she eats them. She has two large black skulls as her companions.

Trivia

 * Ato, a character from the manga Akujiki (also by Sanami Suzuki), makes a cameo appearance in chapter 6. This is confirmed by the author, who noticed the character getting a mention on Japanese Wikipedia's Black★Rock Shooter article.