Maho Hiyajo, a neuroscience and AI researcher at Viktor Chondria University, serves as assistant to Professor Alexis Leskinen. She was a close colleague and friend of the late Kurisu Makise. Born in the US to Japanese parents, Maho retains cultural connections to Okinawa, especially through cuisine. Despite her early twenties age, her 140 cm height and youthful features often cause her to be mistaken for a child, a source of irritation. She possesses long, unkempt black hair with a green tint, green eyes, and favors baggy clothing with mismatched footwear. Once considered a prodigy, Maho began to perceive herself as inferior after Kurisu joined the university, privately comparing their dynamic to the Salieri-Mozart rivalry—a feeling extending to her co-development of the Amadeus AI, which simulated Kurisu's memories. While internally battling jealousy, Maho maintained deep respect for Kurisu; their friendship solidified over shared appreciation for Mozart. After Kurisu's death, Maho inherited her password-protected laptop, which remained inaccessible. She also formed an ongoing relationship with the Amadeus Kurisu simulation, blurring technology and emotion. Her involvement with Rintaro Okabe started professionally when he tested Amadeus. Maho gradually developed romantic feelings for him, complicated by his unresolved trauma over Kurisu's death—a situation teased by Leskinen and Amadeus Kurisu. Maho ultimately accepted Okabe's affections lay elsewhere. A significant subplot saw her form an unexpected friendship with the similarly insecure Moeka Kiryū. This bond deepened during the Twin Automata incident when Moeka sacrificed herself to protect Maho from antagonists targeting Amadeus. This culminated in Maho permanently deleting Amadeus to prevent misuse, signifying her acceptance of Kurisu's death and rejection of a digital surrogate. Maho's technical expertise included reconstructing Kurisu's PhoneWave time travel device from notes and later aiding resistance forces in a dystopian future by providing access to Kurisu's time travel thesis. Her analytical nature was sometimes offset by personal habits like extreme messiness and comedic outbursts when her competence or appearance was challenged. Across world lines, Maho demonstrated resilience. She overcame her inferiority complex through self-reflection and pivotal moments, including Leskinen revealing Kurisu privately admired her dedication. Her arc concluded with her returning to the US, carrying forward Kurisu's unfinished work and determined to forge new scientific paths independent of comparisons to her friend.