

When they finished their mission, Tatsumi asked her what will happen to those girls, she replies that it isn't their problem, but then tells him there is a doctor in the slums who will look after them if she asks him to. Together, they eliminated the gangsters in the building. They enter the targeted building and witness a gang kill a drugged prostitute, a girl who Leone knew from the streets. The two were separated when a gang of men that she had also swindled out of their money came after her, but reunited on time to start their assignment. He realizes that she is very popular in her home district. She is placed with Tatsumi and sent to the Capital to complete their mission. No matter how you dress it up, what we're doing is murder." When they were under attack, Leone stated that her Teigu gives her superhuman strength to beat her enemies to death. He asked what was so funny and Leone replied "Tatsumi. When Tatsumi was given a choice to become part of Night Raid, he wrongly states they are assassins of justice, which caused them to laugh at him. Najenda asked if he showed promise, which Leone affirms. When she meets Najenda, she tells her that she wants to recommend him as a new member of their team. She shows him around the hide-out and introduces him to the other members of Night Raid: Sheele, Mine, Bulat, Lubbock, Akame and Najenda. Still devastated over the loss his beloved childhood friends Sayo and Ieyasu, Leone shows up to cheer him up and to find out if he thought about joining them, but Tatsumi was still hesitant about accepting her offer. After the confrontation at Aria's mansion is concluded, she recognizes Tatsumi's skills and tells him from now on, he'll be a member of Night Raid, serving as a way of paying him back for her earlier conning of him. Later, she reappears and is revealed to be a member of Night Raid. Taking advantage of his naivety at the outset, she tricks him into treating her to dinner and drinks, and then swindles him out of his money. She was the first member of Night Raid to meet Tatsumi in the beginning of the story, offering to get him into the Imperial Army in exchange for a favor. She was apparently scouted by the Revolutionary Army after saving some slum children from a group of nobles who were abusing them for sport. Leone grew up in the slums of the Capital where she had worked in a massage parlor ever since childhood.

She also enjoyed fighting her enemies a lot, as said by Najenda, who told her that she needed to change that habit. Despite the morally-dodgy nature that she sometimes displayed, Leone is not one to tolerate injustice, and can be especially vicious to those who commit the vilest of acts. She serves as a sort of big sister figure to Tatsumi and the younger members in Night Raid, often referring to herself as "Onee-san" or "Big Sis". She had a very relaxed, upbeat, and cheerful personality, and tends to display a lack of lady-like manners, often seen shoving Tatsumi into her breasts, putting her feet on the table, or consuming large amounts of sake and other alcoholic drinks. When her teigu, Lionel, fused with her, her hair becomes longer, and ears a bit bigger, she also sports out lionlike feet and many areas of her body are covered with fur, overall having a more beast-like appearance. When she transformed, her hair becomes longer and she gains lion-like ears, a tail and claws. She wore a revealing outfit with a black tube top, detachable sleeves with what looked like gold bands, pants, boots and a scarf around her neck. She had short blonde hair with two long tufts that framed the sides of her head and golden eyes.
