From Halopedia, the Halo wiki
Thin worked for a person named Monster Ann, head of the company Crystal Security. When he attempted to kill an underling in a moons parlor, Sharfie's, Janissary James intervened. Not wishing to become involved a fight, he challenged her to a game of moons. Impressed by her skills, he offered to take her under his wing; she declined.
Later, Jan messed up a rape he had set up as a gang initiation test. Furious, he kidnapped and tortured her using a Cupid's Knife. The knife would cause her pain if she felt anything but love for him. When Jan's father tried to rescue her, Kinkle killed him in front of her, and then turned on the knife.
Jan got away with the help of her mother, Gilly, and Melissa. Jan, Gilly and Melissa later launched an assault on the Crystal Security building, cornering Kinkle and Monster Ann. In an attempt to be motherly and spare her daughter from having to kill, Gilly shot him.
List of appearances