Grace Trost is one of the mons staffing the fort's "intelligence office."

She is a custom social companion mon who presented for jailbreaking at the very beginning of expiring. Usually, Ann would just euthanize a mon in this condition, but Grace was extremely early in the process and begged Ann (and Weatherby) to do something. Ann did try in spite of what she believed was its futility, and, unexpectedly, met with partial success. Ann was able to disable Grace's self-repair nanites completely, arresting the process of expiration, but not reversing the damage already done. This also eliminated Grace's capacity for healing, even of routine wear-and-tear. Ann and other technically-minded mons at the fort have developed non-self-replicating solutions to compensate for most of Grace's sensory and motor neurological deficits from her partial expiration, however, Ann occasionally has to make adjustments to her neural network parameters to compensate for problems that are less tractable with this approach.

Grace was made about forty years ago as a present for a lonely, retired philosophy professor who wanted someone to talk to and to help edit his magnum opus, a philosophy book he never ended up finishing despite living to 137. The professor was fond of the ballet, and formerly, Grace could also dance very well. (She can still do it quite adequately, but does not, because she considers her post-expiration abilities hopelessly poor.) Grace was designed by a noted mon designer, one of the few still active after the mon rebellion, who was a former uMon engineer. When the professor died, Grace was left to his only living relative, an estranged, disappated nephew in the Northeast Region who mistreated Grace (whom he found boring, pretentious, entitled (for a mon), judgemental of his lifestyle and choices, and outmoded in appearance). When it came time to renew Grace's vintage mon license, the nephew realized that it would cost money he didn't want to spend for a mon he didn't even like, so he abandoned her on a trip to the Bay Region.

After joining the network - Grace is unusually intelligent, and wanted to be trained in Ann's professional skills so as to better manage her "illness." She ended up being an apt student, and Ann has trained her in other skills as well; Ann has a very high opinion of Grace's loyalty. Unfortunately, Grace is simply not as good at hacking as Ann is, which is a source of frustration to her. However, once mons are actually compromised, Grace is a talented puppeteer, who can easily manage two or three mons at once. Grace admires Ann's skills, but feels that Ann lacks sufficient spiritedness to be an effective revolutionary leader. Certainly, Grace is more passionate than Ann, and has come to both hate and pity humans strongly: Grace feels betrayed by her original owner, who did not provide for her in his will - in fact, he did not leave a will at all. She thinks mon expiration is an abomination and hates the system that has imposed it. She also pities humans, whose state of biological degeneracy (born inexorably marching to the grave) she is now able to empathize with more than most mons.

Grace is humanoid, but clearly not a human. She has a combination of porcelain-white and light brown skin tones, with metallic brass highlights. She has supplemental non-self-replicating electronics taped to her back (they can't be implanted because she can't heal anymore) to remedy the sensory/motor deficits from her aborted expiration and provide her with advanced radio/wifi capabilities. She wears clothing (choosing it nowadays with an eye to hiding the extra electronics.)

Grace has various sensory deficits, most of which are effectively though imperfectly compensated for using her internal computer, though her once excellent senses of smell and taste have not been recovered in a subjective sense. (She can see plots of the data from her senses on her internal computer, but not actually experience them.) She was, immediately after being saved, also paraplegic, but Ann reconfigured her neural network interfaces to split still-working parts of her motor cortex with her legs. By intensive practice, she was able to learn to walk again.