The case saw the player and Maddie O'Malley investigating the murder of Italian mobster Joseph Dante, who was found poisoned to death with a makeshift sign claiming he was the "Scarlet Slayer", a serial killer who had been responsible for the murders of several Concordian prostitutes. Xiang was questioned by the detectives after it was discovered that Joseph was a regular client at Xiang's brothel. Xiang responded with hostility, however, claiming she knew little about Joseph personally and accusing the police of doing nothing to protect her girls from the Scarlet Slayer.
Later on, though, it was revealed that Xiang was in actuality responsible for Joseph's murder. When Xiang's prostitutes began to disappear, Xiang investigated their work histories to see who they had been with before their disappearances. After seeing that Joseph was the last client all her missing workers saw before their disappearances, Xiang adamantly came to believe that Joseph was the Scarlet Slayer and decided to kill him to protect her girls. Xiang went about attacking Joseph at the public toilets, stabbing him with a bloodletting knife that was coated in belladonna, with the poison entering Joseph's bloodstream and killing him.
Xiang left traces of her clothing on the case she kept her bloodletting knife in, with this being one of the clues pointing to Xiang's guilt in Joseph's murder. After initially proclaiming innocence, Xiang confessed to killing Joseph, expressing her belief that he was the Scarlet Slayer and that she had been forced to kill him due to the police's disregard for the safety of her employees. Xiang was put on trial, where she pled guilty to Joseph's murder, stating that she protected the prostitutes in her care when no one else would and that they had the same right to be safe as anyone in Concordia. Xiang was ultimately sentenced to seven years in prison, which she accepted, pleased with her belief that her employees were now safe. However, it was later revealed that Joseph was in fact not the Scarlet Slayer, as revealed by the discovery of murdered prostitute Caitlin, who was found killed in the same fashion as the Slayer's other victims.
- (Maddie: "What we're really curious about is what made you so sure it was him...") I did what none of you could, I put the pieces together! After a few girls vanished, I started checking who they had as clients and what they had done before they disappeared. Each girl on my list had spent the night with Mr Dante before she disappeared! And they were booked with him that following day as well! He was always the last person to see them! There's no such thing as coincidence! He murdered them all! (Maddie: "If you had the proof, why didn't you come to us?") I tried, but you did nothing! Your disregard for the safety of my girls forced me to act! I had no choice... so I took care of the Slayer myself!" (Xiang's confession to killing Joseph Dante, under the belief that he was the Scarlet Slayer and that the police wouldn't stop him)
- "He wasn't just Joseph Dante, he was also the Scarlet Slayer, and of that murder, I am guilty as charged! I had to protect my doves because no one else did! They might be considered outcasts, but they had the right to be safe just like every other citizen in Concordia!" (Xiang's statement regarding her motivation in court)