Miri Yobami represents the Yobami branch of the Hundred Devouring Families. Her family, alongside the Inbami family, dominates the medicine and poison trade, a source of historical conflict within the Momobami clan. She arrived at Hyakkaou Private Academy to compete in the presidential election, aiming to replace Kirari Momobami as Student Council President and select a new clan leader. Physically, Miri is short with dark blue hair styled in two odango buns. Her dark blue eyes appear empty, accentuated by distinctive red eye shadow at the corners, mirroring Miyo Inbami's makeup. She wears the standard Hyakkaou female uniform. Miri is quietly unsympathetic and reserved, maintaining cold distance and rarely speaking in full sentences to outsiders. Her defining trait is profound loyalty to Miyo Inbami, whom she considers a sister. Their bond formed in childhood after their families, lacking heirs, named them clan heads and forcibly separated them. Forbidden from speaking during family meetings, they created a private sign language for discreet communication. They use this language to coordinate seamlessly during gambles, exhibiting near-telepathic teamwork. During the presidential election, Miri and Miyo poisoned and defeated Yuriko Nishinotouin, dismissing her as "fragile" for breaking down too easily. They later faced Yumeko Jabami and Ryota Suzui in the Nim Type Zero game. Miri declared them enemies, dispensing with formalities. She remained strategically focused throughout, showing no concern when Yumeko suffered poison effects. When Miyo introduced poisoned needles as stakes, Miri complied despite the danger. Following Miyo's command to lose intentionally to protect Miyo's election standing, Miri accepted defeat. This eliminated her from the race and cost her all votes. She fell unconscious from the poison but received an antidote from Miyo and was hospitalized. After recovering, Miri attended the election auction but refrained from further gambling. She watched subsequent events, expressing concern during Miyo's match against Mary Saotome in the Grand Tournament. She also noted the group's underestimation of Rei Batsubami. Though inactive, she continued monitoring the election's outcome. Her surname, Yobami (陽喰), combines "light, sun, male" (陽) and "bite" (喰), forming the "yang" counterpart to Miyo Inbami's "yin"-themed surname. Her given name means "three" (三) and "reason, logic" (理).