OVA
Description
Chan, also known as Rosarita Cisneros, is a central figure in the Black Lagoon: Roberta's Blood Trail arc. She works as a maid for the Lovelace family, a powerful Colombian household, and is the former caretaker and protector of its young heir, Garcia Lovelace. Prior to her life as a domestic servant, Chan was a fearsome guerrilla fighter and assassin trained in Cuba as a member of the FARC. In this past life, she was known as Rosarita Cisneros, an internationally wanted criminal whose reputation earned her the moniker "Bloodhound of Florencia" for her relentless and brutal efficiency.

Her personality is a stark contradiction of a deeply caring and loyal individual with a dormant, monstrous capacity for violence. Within the Lovelace household, she shows great warmth, kindness, and devotion, particularly to Garcia, with whom she shares a close bond. However, this gentle exterior masks a tormented soul haunted by her past sins. She has a reputation for being a "hardcore terrorist," and figures like Revy regard her as a psychotic threat. During her rampage, she begins consuming stimulant drugs heavily and suffers from hallucinations of her previous victims, showing a complete disintegration of her sanity. Her once-controlled ferocity becomes that of a "stray wolf," as her ability to distinguish friend from foe grows dangerously unstable.

Chans primary motivation in Roberta's Blood Trail is revenge. Following the assassination of her master, Diego Lovelace, by a U.S. Special Forces team, she abandons her peaceful life and returns to Roanapur to hunt down the killers. Her goal is not merely to kill them but to exact a brutal and personal atonement for her failure to protect the Lovelace family. As her quest progresses, her mission becomes twisted with a desire to punish herself for her past atrocities, blurring the lines between justice and a suicidal end.

Within the storys conflict, Chan acts as a rogue agent of chaos. Her return to Roanapur threatens to ignite a city-wide war between the local criminal syndicates, including Hotel Moscow and the Triad, and the American military, who are operating in the area. The narrative forces other characters, particularly Rock and the Lagoon Company, to intervene not to support her, but to contain the destruction she is causing. Her course is in direct opposition to the efforts of Garcia and her fellow maid, Fabiola Iglesias, who come to Roanapur specifically to bring her home and save her from herself.

Her most significant relationship is with Garcia Lovelace. He is the reason she joined the household and the person she is sworn to protect. She views him as a source of redemption and humanity. In the anime adaptation of the arc, the climax of this relationship comes when her sanity fractures to the point that she nearly kills him, and it is ultimately his intervention that forces her to stop. Her dynamic with Rock and Revy is also central, as she represents a mirror image of their own potential fates, a warrior consumed by the very violence she wields. Rock attempts to manipulate the situation for a diplomatic solution, while Revy sees in Chan a reflection of her own "smell of blood, gunpowder and muck".

Throughout the OVA, Chan undergoes a drastic and tragic development. She transforms from a disciplined, domesticated maid back into a full-blown, psychotic guerrilla fighter. Her physical and mental deterioration is extreme, involving drug abuse and a loss of identity, showing her trauma consuming her piece by piece. While the manga offers a cleaner ending where she recovers, the anime adaptation concludes with her survival, albeit at a devastating cost. In the anime, she loses her right eye, her right leg, her left arm, and some fingers. This physical destruction serves as a permanent scar of her relapse, but she is last seen alive alongside Garcia, hinting at a fragile return to peace.

As a combatant, Chan possesses abilities that border on superhuman. Despite being untrained as a maid, she is a master of virtually every form of weaponry. Her arsenal includes anti-material sniper rifles fired one-handed, shotguns disguised as umbrellas, machine guns hidden in suitcases, and various knives and pistols. Her physical prowess is such that she can shatter a chainsaw blade with her pistols and catch a metal blade in her mouth. She demonstrates incredible endurance, durability, and a relentless predatory instinct, attributes that make her one of the most dangerous characters in the series, even as she loses herself to her own fury.