Doll Isamu emerges as the third Doll Knight in the series, initially bound to antagonist Devaul’s command before liberation redirects their allegiance to the protagonists. They wield the massive blade Light Thunder, a weapon that cleaves through foes and unleashes devastating energy projectiles mid-combat. Summoned via a blue bracelet known as the Calling Watch, their activation hinges on the incantation *Pereso Perese Burune Buraine*.

Mid-series, under Devaul’s influence, they confront Licca Kayama as part of the antagonistic forces, clashing directly with fellow Doll Knights until Doll Licca shatters Devaul’s control. Freed from manipulation, Isamu pledges service to Dai Takabayashi, Licca’s ally, dedicating their strength to safeguard Licca’s cause.

This role persists through later media, including the film *Licca-chan Zettai Zetsumei! Doll Knights no Kiseki*, where Isamu joins their fellow Knights to face resurgent threats like the revived witch Dana. No documented expansions to their arc or history exist beyond these core narratives.