Luca is a calico cat who serves as the co-pilot and companion of Amy Stapleton, the midfielder and tactician for Team Satomi in the Immortal Grand Prix. Found abandoned by Amy at a young age, Luca was taken in and the two have been inseparable ever since. He has a cybernetic brain that allows him to communicate directly with Amy when linked to her mech, forming a composite personality during races. Through this neural synchronization, Luca becomes an active participant in the team's strategy and performance, giving Amy and the rest of the team a unique edge on the track.

Luca is quiet and loyal, showing fierce dedication to Amy and the team. He rarely vocalizes beyond his bond with Amy, but his presence is felt through decisive action in high-pressure moments, such as taking control of the mech to knock out an opponent in the original microseries. His motivations are simple: to support Amy and help Team Satomi succeed. His role is that of a trusted partner and auxiliary pilot, providing tactical insight and a calming influence that balances Amy's more analytical nature.

Key relationships center on Amy, his closest friend and handler, and over time, the other members of Team Satomi. Initially, only Amy could hear Luca's voice, but by the start of the 2051 racing season, all team members are able to hear him, marking a development in his integration with the group. This expansion of communication demonstrates his growing role as a true team asset rather than a one-on-one partner. In terms of notable abilities, Luca's cybernetic brain enables mind-to-mech interfacing, communication through the team's neural link, and a heightened situational awareness that complements Amy's tactical planning. His agility and instinct as a cat, combined with his cybernetic enhancements, make him a valuable contributor to Team Satomi's rise in the IG-1 league.