"Gunslinger Girl" is a Japanese manga series created by Yu Aida. It follows a secret government program that transforms young girls into highly skilled assassins, known as Fratello, who are paired with male handlers. The story explores themes of loyalty, identity, and the moral implications of using children for combat. Set in a near-future Italy, the series combines action with emotional depth, showcasing the girls' struggles as they navigate their new lives. Each character has a unique backstory, highlighting their pasts and the impact of their training on their humanity and relationships with their handlers.