Before becoming a full-time Contractor operative, Mao originally traveled to Japan as a student. He returned shortly before the appearance of Hell’s Gate, during which time he had a brief encounter with Asako Nakimiya in Ikebukuro. His life changed dramatically after being recruited by a faction within the Syndicate while studying at a university in Moscow. Mao was assigned to investigate Mikhail Pavlichenko and his research, a mission that ultimately led to his betrayal.

During a confrontation at Mikhail’s laboratory, an explosion destroyed Mao’s human body. Stripped of his physical form, he survived by transferring his consciousness into the body of a black cat using a neural link device. Enraged by his betrayal, he lashed out at Mikhail amidst the lab’s destruction. From that point forward, Mao began switching between various animal hosts, though he most often resided in the body of the black cat for operational purposes.

Because an animal’s brain cannot fully support his human consciousness, Mao relies on an external server system to maintain his mental stability. If this connection is severed, the animal’s instincts gradually override his own, and he loses his sense of self until the link is restored. This vulnerability is a constant risk and serves as a reminder of the cost he paid for survival.

As a Contractor, Mao is highly rational and pragmatic, typically making decisions based on logic rather than emotion. This trait is characteristic of most Contractors and often puts him at odds with Hei, whose emotional responses and unpredictable behavior fascinate Mao. He frequently observes Hei’s actions with curiosity, struggling to fully understand his motivations but intrigued by his human tendencies.

Though Mao serves the Syndicate, he harbors a degree of skepticism toward its leadership. He is aware of the consequences of defying orders and occasionally receives directives directly from upper management. Nevertheless, Mao demonstrates a strong sense of loyalty to his comrades, often choosing to withhold sensitive information from the Syndicate in order to protect his team.

Despite his stoic and analytical nature, Mao exhibits subtle quirks most notably, an unusual attraction to ankles. This fixation is so distinct that he once identified someone by their ankles after more than a decade had passed, adding a rare touch of humor to his otherwise serious role.

Mao no longer possesses a human body and instead resides within the bodies of various animals using a neural link device. For most of the series, he inhabits the form of a small black cat with sleek fur, sharp green eyes, and a red collar fitted with communication equipment. The cat’s appearance is unassuming, allowing Mao to operate effectively in reconnaissance and stealth-based missions.

After the death of the black cat, Mao transfers his consciousness into a brown momonga (Japanese dwarf flying squirrel). In this form, he retains his mobility and ability to observe situations discreetly, though his physical capabilities remain limited compared to his human origins.

Animal Possession
Mao’s Contractor ability allows him to transfer his consciousness into the bodies of animals, provided they are within his line of sight. This unique power enables him to function as a covert operative, often using inconspicuous hosts such as cats or squirrels for surveillance and infiltration.

Neural Interface and Server Link
Because an animal’s brain is not capable of fully supporting a human-level consciousness, Mao relies on a remote server network to supplement his cognitive functions. He must periodically connect to this server by entering a trance-like state, during which he downloads a necessary data pack to maintain his personality and memories. If he is disconnected from the network for too long, the animal’s natural instincts begin to override his human mind, causing him to lose self-awareness until the connection is restored.

This ability makes Mao highly valuable for intelligence gathering and reconnaissance, though it comes at the cost of constant vulnerability to network disruption and the fragility of his host body.