Through the Retro CDs, Gregory is portrayed as being quiet and introverted, and prefers the room to be dark; One of his therapists specifically considers him to be more of a loner. He's also portrayed as a capable and manipulative hacker, and particularly alert. According to his files, he was good at self-dialogue, getting answers by asking himself questions. He also likes watching sports, but not playing them.

During the events of Security Breach, he's much more talkative with Freddy than he was during the CDs, and is shown to be reckless at times.

During the Security Breach: Ruin DLC, Gregory is shown to be artistic, making comic strips of five of the six Security Breach endings; Cassie also believes he should be an artist when he grows up. Glamrock Freddy is also stated to be his favorite of the Glamrocks, though it's unclear whether this was because of the events of Security Breach, or if Freddy was his favorite even before that.