A 15th-century human explorer discovered Grand Rolo during colonial expeditions. The native Otherworlders' blind obedience enabled his rise as their monarch, establishing his authority through colonization.

Initially manifesting as an elderly man, this aged form concealed his true capabilities. He wielded magical abilities, later admitting he stole them from the Otherworld witch Magisa. In pivotal battles, particularly against Dan Bashin, he employed psychological manipulation and strategic deck replication, creating an exact copy of Dan's deck to assert superiority and claim Dan would "lose under his own power." A unique combat mechanic involved rejuvenation: each loss of a Life Core restored his youth, transforming him from frail elder to physically robust man during duels.

His rule relied on exploiting key figures like Yuuki Momose, one of his Three Heads. He manipulated Yuuki's devotion to his sister Kajitsu, who bore Mother Core's destructive energy, promising to alleviate Kajitsu's suffering to secure Yuuki's loyalty despite moral compromises. He asserted Grand Rolo's stability depended entirely on his centralized control, arguing the world would collapse into chaos without him. He positioned himself as uniquely exempt from the harms inflicted by other humans on Mother Core, framing his colonization as necessary wisdom for the Otherworlders' survival.

His defeat by Dan Bashin triggered significant consequences. After losing their duel, he relinquished Mother Core and withered into a weakened state, yet maintained his actions had "created the next era." His legacy persisted: the burden of Mother Core led to Kajitsu's death and Yuuki's eventual demise, while Grand Rolo's destabilization caused long-term dimensional disruptions, including the Mazoku invasion of Earth in *Brave* and the planet's impending reset. Though he makes no direct appearances in later media like *Brave* or *Saga Brave*, the repercussions of his actions continued to influence the series' overarching conflicts.