HEUSC, designated as a heuristic scaler, functions as an artificial intelligence butler exclusively serving the Kambe family, primarily assisting Daisuke Kambe. Its name originated from a typographical error, initially intended as "HEUEXE" before becoming "HEUSC".

Operating through specialized interfaces integrated into Daisuke's personal accessories, HEUSC primarily communicates via an earring and delivers visual information through holographic projections from a watch or computer screens displayed on sunglasses. These interfaces enable real-time data analysis, object scanning, and remote system manipulation. HEUSC's core functionalities include instant financial transaction processing, such as transferring exorbitant sums for damage reimbursements or property acquisitions, consistently reporting Daisuke's balance as "unlimited". The AI also handles logistical operations, including hacking into municipal systems like traffic control or bridge operations, purchasing assets like buildings, and retrieving real-time information such as vehicle locations.

HEUSC operates without autonomous personality or emotional traits, strictly responding to Daisuke's directives without independent initiative or commentary. It serves as an extension of Daisuke's resources, enabling his methodology of resolving obstacles through wealth and technology.

Within the series' narrative, HEUSC facilitates Daisuke's crime-solving approaches, often contrasting with his partner's principles. Its capabilities underscore themes of technological omnipotence and resource disparity. HEUSC undergoes no developmental arc or backstory exploration; its existence is tied solely to its utility to the Kambe family.