Damian served as a soldier within the Bioterrorism Security Assessment Alliance's elite Silver Dagger unit, commanded by Captain Chris Redfield. His extensive military background included prior service in the U.S. Special Forces alongside his comrade D.C., forging a significant personal and professional bond. Off-duty, Damian and D.C. shared a close friendship, frequently discussing their favorite television series, *Breaking Bad*. Described as a natural-born soldier and hunter, Damian struggled to envision a life without conflict. He possessed a sarcastic and sensitive personality beneath a hardened exterior, pursued hunting as a personal hobby, and owned a lodge in Canada.

Damian participated in critical Silver Dagger operations. He assisted in the recovery of Professor Rebecca Chambers from a bioterror-attacked university in Chicago, Illinois, engaging in combat against zombies. Subsequently, the unit deployed to Colorado after identifying similarities between the Animality Virus and the Las Plagas parasite. There, Damian joined Chris Redfield and Leon S. Kennedy in operations to destroy A-GUA trucks dispersing the virus, utilizing the knowledge that high temperatures could neutralize the pathogen. During these missions, the group eliminated agents working for the bioterrorist Glenn Arias.

Damian's final mission occurred during Glenn Arias' orchestrated New York City outbreak. Tasked with destroying tanker trucks dispersing the A-Virus aerosol across the city, he successfully destroyed one tanker. While investigating a suspicious van linked to Arias' mercenaries, two Doberman hounds infected with the A-Virus attacked. One zombie dog savagely mauled Damian, decapitating him. His death occurred in the presence of Chris Redfield and Leon Kennedy; Kennedy created a distraction to facilitate escape while Redfield mourned the loss.

Damian's character portrayal remained consistent, emphasizing his dedication as a soldier and loyalty within the Silver Dagger unit.