Hakase, known as the Professor, is a renowned elderly scientist and inventor distinguished by his balloon-shaped nose, bushy grayish-white mustache, and signature attire: a lab coat draped over a yellow shirt and red tie. His wardrobe occasionally shifts, such as swapping his coat for a tropical orange shirt during vacations. He engineered pivotal technologies like the Time Station, Peak Point Helmet, and AI Casi, tools critical in thwarting threats from adversaries.

As Natalie’s grandfather, he balances warm paternal guidance with a penchant for forgetfulness and clumsiness. Though his oversights—such as misplacing the Peak Point Helmet prototype, enabling Specter’s theft—create vulnerabilities, his altruistic intentions remain steadfast, prioritizing global security and his allies’ safety. His inventions, including the Time Net, Stun Club, and R.C. Car, demand creative deployment by protagonists, often distributed during training sessions or mission briefings.

Antagonists like Specter repeatedly target him, once imprisoning him in a circus cage at Specter Land until a clash with a robotic clown prompted his rescue. His narrative role shifts across adaptations: he alternately serves as mission control, guides allies remotely, or is sidelined by external threats—such as Specter’s hypnotic broadcasts—forcing substitutes like Aki to take his place.

In spin-offs, his involvement varies from brief cameos to direct action, such as dispatching a combat-trained Pipo Monkey against mechanized foes in *Mesal Gear Solid*. His legacy is marked by unintended consequences, as his innovations inadvertently trigger global crises, though he avoids direct blame.

Unofficial fan theories speculate on personal details, like a birthday linked to an anime episode’s air date. Regional releases occasionally misname him (e.g., "Dr. Zizel") due to graphical errors, though canonical sources consistently affirm his identity across iterations.