Kerberos holds no resemblance whatsoever to his old persona. Though he had no second thoughts when he first took the red pill that would set him free, his actual emergence from the Matrix and into the real world of destruction and machines was much, much more than he had bargained for. His mind did not snap from the sudden drop into inconceivable circumstances, but it did withdraw into itself in seemingly irreversible trauma, leaving behind a quiet young man who seems mentally retarded at most times. When not being spoken to or otherwise interacted with, Kerbie sits in the quietest corner of the Lazarus that he can find, lost in whatever bleak thoughts now occupy his mind, with his eyes unblinkingly downcast. He responds when spoken to, though he rarely speaks more than a handful of words at a time, and acts upon commands and requests with a kind of dazed willingness. Sometimes he is struck by fits of tears and paranoia unsuited for a young man his age, but only when he is left in solitude for too long. At other times he will 'wake' into a kind of childlike curiosity, and watch someone or something with rapt, unfaltering attention, but he always drops back into his mental solitude after a while.

The only thing that completely pulls Kerberos from his stupor is to be seated in the Lazarus's operator's chair and told to get to work. In his states of curious attentiveness, Kerbie picked up the methods of reading the Matrix's code like a prodigy, and he can manipulate programs and find exits for the crew with the best of them. When doing his job in front of those monitors, Kerberos is an entirely different person, nothing like Chase used to be but still a great improvement from withdrawn little Kerbie. He responds to questions and requests like a pro, articulating complete and thorough sentences, and solves problems for his plugged-in comrades in the space of a blink. But Kerberos is little more than an idiot savant, for the moment he turns from the monitors and has no more reason to read the code, he again becomes inscrutable and silent.

Kerbie is obsessed with keeping himself covered, and clothes himself in every scrap of attire he can get his hands on--not to hide himself from others' eyes, but to hide from his own. He could not stand his first sight of himself, naked and hairless with sockets grafted to his flesh, and since then has been fanatical about concealing his body. The fraying cap he wears was in fact scrounged from the cabin of an ex-crewmate, to hide his cranial plug. Even when clothed in his multiple layers, Kerbie will not look at his own reflection and pointedly avoids looking at any mirror-like surface.