Gen Asagiri, a former professional mentalist and magician from modern Japan, was petrified during a live television broadcast. Depetrified millennia later in 5739 by Tsukasa Shishio, he initially acted as a spy for the Tsukasa Empire, tasked with confirming Senku Ishigami's death. Witnessing the creation of electricity and iron in Ishigami Village, however, prompted Gen to negotiate an alliance with Senku in exchange for cola. He then embedded himself within the Kingdom of Science, providing false reports to Tsukasa about Senku's demise. Physically, Gen presents as a slim young man of average height with pale skin. His most distinctive feature is his bicolored hair—black on the left and white on the right, a change occurring post-petrification. He has angular, shadowed eyes resembling eyeliner. A jagged petrification scar originally marked his left cheek; it healed after his second depetrification, but he later recreated it with paint. His attire typically consists of a lavender-pink overcoat layered over a wheat-colored yukata, tied with an orange obi and thin rope. He often goes barefoot but later adopts sack-like shoes similar to Senku's. Gen's personality balances calculated manipulation with genuine loyalty. He self-identifies as an opportunist, prioritizing personal comfort and avoiding labor. His expertise in psychology allows him to read people, predict behavior, and orchestrate complex deceptions, such as faking his own death using concealed blood packs. Despite his self-serving facade, he demonstrates unwavering commitment to the Kingdom of Science, risking his safety for allies like Taiju. He exhibits quirks like speaking in playful Pig Latin and reacting theatrically to scientific revelations. His skills include proficiency in psychology, manipulation, and lie detection, enabling him to deceive polygraph tests. He excels in stage magic, sleight of hand, and impersonation, convincingly mimicking voices, including female tones. Gen is fluent in Japanese and English and adept in Morse code, which he employs for covert communication. While lacking Senku's scientific acumen, he bridges gaps between scientists and laypeople, translating complex concepts. His endurance is notable, surviving severe injuries and long treks. Key relationships define his development. He respects Senku Ishigami's intellect and vision, evolving from a transactional ally to a trusted confidant; he built a telescope for Senku's birthday, symbolizing genuine admiration. Their dynamic complements Senku's scientific rigor with Gen's psychological insight. Initially viewing Tsukasa Shishio as a dangerous dictator, Gen later achieves mutual respect after Tsukasa joins the Kingdom. Early interactions with Kohaku involved distrust and threats, but they develop mutual reliance, teasing each other while coordinating in crises. Gen shares an unexpected bond with the village craftsman Kaseki, frequently assisting him despite attempts to avoid work; Kaseki's insistence overrides Gen's reluctance. Gen aided Chrome during village competitions, using deception to help him defeat Magma; their partnership strengthens during missions like planting communication devices. In the "Dr. Stone: Ryusui" narrative, Gen facilitates economic systems by introducing "Dragos" currency and orchestrating a hot-air balloon expedition. He manipulates Ryusui Nanami into funding the voyage by rigging a card draw, ensuring Chrome's participation. Character development reveals deeper empathy: he expressed awe upon discovering platinum collected by Senku's father, recognizing its emotional significance. When Taiju suffered critical injuries, Gen displayed visible distress. Moments like surrendering to Xeno with a white flag underscore his strategic loyalty to the Kingdom's ideals.