Miyo Inbami is a member of the Hundred Devouring Families' Inbami clan, specialists in pharmaceuticals and poisons. Separated from her sister Miri Yobami in childhood when both were named clan heads to secure positions within the Momobami clan, Miyo and Miri developed a private sign language to communicate silently during forbidden verbal interactions at family meetings. Their bond remains central to Miyo's motivations. **Appearance** Miyo possesses very long black hair (depicted as dark blue in the anime), typically secured in a bun with one long strand extending to her waist. Her distinctive makeup features red eyeshadow, lip gloss, and red-painted fingernails. She wears the standard female uniform of Hyakkaou Private Academy, usually paired with brown low-heeled shoes instead of loafers. **Personality and Traits** Miyo presents a polite, sophisticated façade masking a ruthless and arrogant core. She views gambling as trivial, readily employing violence or poisoning to win without remorse, even endangering family. While prioritizing Miri's safety and manipulating situations to protect her, Miyo simultaneously believes in her own superiority, including over Miri, and sacrifices her sister to advance personal goals. After defeats, she exhibits grudging respect for adversaries like Mary Saotome, acknowledging their determination. **Actions and Development** During Hyakkaou Academy's presidential election, Miyo and Miri poisoned opponent Yuriko Nishinotouin to claim her votes. Facing Yumeko Jabami and Ryota Suzui in "Nim Type Zero," Miyo poisoned Yumeko preemptively. When Mary Saotome replaced Yumeko, Miyo escalated the gamble using poisoned needles and antidotes as betting chips. After Mary exposed their sign-language cheating, Miyo forced Miri to take a loss, causing Miri's collapse. Miyo later poisoned Miri again to "ensure fairness" before rushing her to safety. In the election tournament, Miyo poisoned opponent Ibara Obami during "Rock Paper Scissors Poker" and colluded with Erimi Mushibami to rig card games. Against Mary in a later gamble, she marked cards with needle holes for an advantage. Cornered when Mary detected her cheating, Miyo ingested a lethal poison pill, threatening mutual demise unless Mary conceded. Miri intervened with an antidote, causing Miyo's defeat. This act highlighted Miyo's despair over potentially losing her reunited time with Miri. Post-defeat, Miyo displayed subtle development: she acknowledged Mary's resilience, refrained from further gambles to focus on supporting Miri, and participated in the clan's 100-vote auction, cautioning allies against underestimating adversaries like Rei Batsubami. **Abilities** Miyo leverages her Inbami pharmaceutical expertise to create undetectable poisons and antidotes. Her private sign language with Miri enables covert coordination during gambles. She excels at psychological manipulation, card marking, and high-risk strategies, such as leveraging her own survival against opponents.