Chris is Leon's much younger brother – their mother became pregnant with Chris when she was fifty, and died during childbirth. As a result, Chris was raised by his aunt and uncle, who he grew up calling "Mom" and "Dad". When Chris' younger cousin, Sam, told him that he was responsible for his mother's death, he was so shocked that he lost his ability to speak. Chris was sent to Los Angeles with Leon and spends most of his time in D's pet shop. Although he can't talk, Chris has the ability to telepathically speak to all of D's animals as well as the Count and, eventually, Leon. He also thinks very highly of Q-chan saying that he was "The cutest, rarest, and highest priced pet in the shop," though as it turns out, Q-chan is the only "pet" Chris perceives as an animal. Since he initially only ever sees the animals in their human form, he believes that the Count actually sells human children, although he feels all right with that as long as the children don't mind it.
In Volume 10, Chris reconciles with his cousin, regains his ability to speak, and moves back to his aunt's house. This comes at the price of his loss of ability to see the animals in their humanoid forms, referred to in the manga as something of a "Departure from Eden". Twenty years later, he is shown as an FBI officer, tracking down the next generation of the Count's family. Rather than trying to arrest "New D" for the mysterious deaths caused by a pet, Chris only wishes to talk about his brother who disappeared 20 years ago. He does not seem to regard "New D" in an adversarial light the way his brother Leon regarded Count D or Agent Howell regarded Papa D. It seems that he remembers the Pet Shop in a positive light.