Hiiragi Ichirou, alias "The Florist," is a middle-aged survival game participant compelled to win funds for his daughter Suzune’s life-saving treatment for a congenital heart defect—a condition he shares, intensifying his desperation. Initially framed as an antagonist, he wields the Sigil "Meg Mell," granting dominion over plant life to craft offensive vines, bulletproof armor, explosive-resistant barricades, and narcotic-infused traps capable of manipulating targets, though their compliance limits this control.

During a treasure hunt, his clash with competitors Kaname Sudō and Rein Kashiwagi pivots to an uneasy alliance against the Eighth Clan, a rival faction hunting the same resources. His tactical ingenuity emerges as he transforms a hotel into a plant-fortified stronghold, orchestrating counterattacks to stall enemy forces. Though his methods blur ethical lines, his motives anchor firmly in securing Suzune’s future, painting him as a pragmatist entangled in moral gray zones.

In the event’s climax, he stages a sacrificial last stand against the Eighth Clan, enduring mortal wounds to unleash his Sigil’s full power, collapsing the hotel to crush adversaries. His demise spotlights the game’s brutal stakes and the extremes of parental devotion. Suzune later inherits indirect involvement in the game, though her path remains ambiguously documented.

Hiiragi’s arc evolves from solitary ruthlessness to collaborative defiance, balancing survivalist cunning with emerging loyalty to allies. His duality—ruthless strategist and devoted father—mirrors the game’s inherent moral conflicts, framing sacrifice as both destructive and redemptive.