Shinazu no Ryouken takes place in a world where humans are immortal. No matter how serious an injury someone receives, they will be revived. However, things take a turn for the people in this world when a new disease called RDS causes the people to lose immortality. People contract RDS when they fall in love with a human from another world called a Vector. The Anti-Vector Police Task Force is created to hunt down and exterminate the Vectors that are trying to blend in with society. The Vector's only hope is a group of gun-wielding girls called Escape Artists, who help Vectors escape from the police. The story follows Detective Kenzaki as he tries to find out the truth behind RDS and the Vectors while battling against the Escape Artist Rin.

Gunslinger Girl and Shinazu no Ryouken are both centered around organizations who train young girls as assassins and use them to carry out various missions. Much like the girls of the Social Welfare Agency, the Escape Artists have little knowledge of their pasts and have been trained to kill. As the girls in both series go about their daily lives as weapons, they start to question the reason for their existence and if what they are doing is right. Rin and Kenzaki share a similar relationship to the Handlers and Cyborgs of Gunslinger Girl. Rin and Kenzaki’s relationship is built on the regrets Kenzaki has about his past that lead him to become involved with Rin, similar to how the Handlers are seen to have picked their Cyborg partners based on things that happened in their pasts.

On a mysterious and prohibited island known as Dragon's Beak, there is said to be the power of the gods, that gives the person who obtains the power to have all of their wishes will be granted. Many people travel to Dragon's Beak in hopes of attaining, but nobody who goes to the island ever gets off of it. With not only monsters on the island but also a group of people with supernatural powers called Takers, immortal beings who fight alongside their Valors against the monsters and the people who go to the island. As the Takers Kai and Jack, along with their Valors, Alice and Dorothy, are tasked by the government to protect the island from anyone who would try to obtain the powers that could be found there.

Drug-on is much more focused on its supernatural elements as opposed to Gunslinger Girl, which is a much more realistic manga. Drug-on and Gunslinger Girl find their similarities in the characters and their relationships. Alice is shown to be alike Henrietta, with both of them developing romantic feelings for their partner, but their partners only see them as tools to be used. Kai also shares some similarities with the girls from Gunslinger Girl. Kai goes through a similar journey we see the many go the girls go through as Kai starts to question why he has his powers and why he exists in the first place. While there is a decent amount of action in each manga, Drug-on and Gunslinger Girl focus more on the characters relationships and digging into their emotions.

Kuroe Kurose is a former vampire hunter who is now living as a private detective and an author who gained the power to see things nobody else could see after he was attacked by a vampire. He lives his days working and taking care of a young girl named Misaki Minato who has just recently been turned into a vampire. Kuroe's job leads him into dangerous situations where he must fight against vampires and other supernatural creatures much to Misaki's dismay. Misaki has to deal with her newfound vampire powers and must decide if she will use her powers to turn Kuroe into her Reinfield, granting him some of her vampire powers to keep Kuroe safe.

Blood Alone is another manga that features a young girl that has gained powers and uses them to fight. Misaki is a very similar character to Henrietta, with both of them falling in love with the person that takes care for them.
Kuroe and Jose are very similar as they both end up pursuing dangerous careers after the deaths of their sister's at the hands of the antagonists of the series. Both manga focus on the relationship between their main characters as the characters try to live somewhat normal lives despite the dark situations they find themselves in . Blood Alone builds up its relationship in a much more romantic way than how the relationships between the handlers and cyborgs happen in Gunslinger Girl, but both manga give off a very similar vibe.

Tista Lone is a quiet college student living in New York City who dreams of being a teacher. Tista seems to be living a normal life, but she has a secret that nobody could imagine. As Tista grew up in a Catholic orphanage, she was trained to be an assassin who kills the worst of the worst from the shady underbelly of the city. When on assignment, Tista goes by Sister Militia and her ability to snipe people from incredibly long distances and her numerous killings of evil-doers has caused her to be labeled a serial killer by the New York City police. Tista's everyday life outside of her Sister Militia persona was uneventful until a young artist named Arty Drowa saves her from a car accident and befriends her. When Arty gets caught up in one of Tista's missions, she begins to struggle with balancing her lives as Tista and Sister Militia.

Tista and Gunslinger Girl are both about young girls who are trained to be assassins to fight against criminals. Both manga deal with some darker themes including drug trafficking and a whole lot of blood. The stories start out fairly similar with young girls that have troubled pasts are taken in to become assassins, but after that, the stories take different approaches to telling their stories. Gunslinger Girl is more of a slow-burning thriller that makes you think, while Tista is much faster paced and at times almost comedic. Despite these differences, the stories still go through arcs with the characters starting out as little more than just emotionless assassins that develop into much deeper characters as the story progresses with the main girls eventually come to question their existence and go through trials to accept their place in the world ultimately coming out stronger than they had ever been before.

Gohongi just moved back to his hometown, but it isn't quite how he remembered. Two mafia fractions have been battling for control of the city. Gohongi gets wrapped up in the mafia when a 15-year-old girl named Mei and Katsura move into the video rental store where Gohongi has been staying. Gohongi soon learns that Mei and Katsura are members of the mafia, Lovely Town. After seeing Mei kill somebody, Gohongi tries to get her to leave Lovely Town and do something else with her life. After getting closer to Mei and Katsura, Gohongi starts to get more involved with Lovely Town than he ever wanted.

Girl May Kill features many of the same elements as Gunslinger Girl, but Girl May Kill uses more comedy and lighthearted scenes. With its lighter tone, Girl May Kill gives a different perspective on the young girl turned than any other manga on this list, but it still provides the reader with all of the aspects that made Gunslinger Girl great. Girl May Kill uses a similar ratio of action to character development to Gunslinger Girl choosing to focus more on the development of Gohongi and Mei with a sprinkling of action scenes. Girl May Kill also deals a lot with the morality behind using young girls as weapons.

Sometime in the future, an unlikely group of allies searchers for the answers to the pasts in the dark underground of the city. The group of Mihai, Haine, Badou, and Naoto have all come to the city for different reasons. They eventually come together due to their pasts being tied to the underground of the city. The four of them band together to fight against the organization that controls the underground in hopes of finding the secrets to their pasts.

Dogs: Bullets & Carnage takes a huge step away from the other manga on this list. Lacking the killer young girls that have filled this list, the connections Dogs: Bullets & Carnage has with Gunslinger Girl are on a whole different level. Both manga are extremely dark, featuring bad guys who take part in some of the worst activities imaginable, letting the reader cheer for the defeat of even the smallest of villians in the series. Both manga also features main characters that have been heavily experimented on increasing their powers and allowing them to fight against the evils in the world. Dogs: Bullets & Carnage also has a similar aesthetic to Gunslinger Girl as both manga take places in various places in Europe