Melchisedec, known as Melchi, serves as a childlike mechanic for the Basion Academy forces. Working with associate Carmichael, Melchi locates and rebuilds the heavily damaged Strain unit Ram-Dass within their ship's storage area. During this project, Melchi installs a recovered Mimic core—a device essential for piloting Strains—into a salvaged porcelain doll. Sara Werec later names this doll Emily.

Melchi's technical expertise proves vital when Sara, despite losing her original Mimic, successfully links with the Emily-integrated core to pilot the reconstructed Ram-Dass. Melchi then advocates for Sara's reinstatement as a Strain pilot, overcoming initial command objections.

Personality-wise, Melchi displays eccentric tendencies, frequently engaging in playful arguments with Carmichael. These exchanges often feature the recurring phrase "Shut up, Carmichael" during disagreements or teasing. Though unconventional, Melchi's consistent delivery of crucial technical solutions—enhancing combat survival odds—earns tolerance from superiors.