OVA
Description
Hajime Nagumo was initially a 17-year-old Japanese high school student possessing an average academic record and a relaxed demeanor. His parents—a video game developer father and manga artist mother—shaped his otaku interests in gaming and pop culture through their creative professions. He secured part-time roles at their companies, establishing his future career trajectory. School life brought bullying from peers like Daisuke Hiyama, stemming from his proximity to class idol Kaori Shirasaki, which resulted in social isolation. Nevertheless, he exhibited a self-sacrificing nature, consistently prioritizing others' safety above his own.
During a class expedition to the fantasy realm Tortus, Hajime and peers were summoned by the deity Ehit. While classmates gained combat abilities, he received the non-combat "Synergist" role, capable of basic alchemy and material transmutation, intensifying his marginalization. His pivotal moment unfolded in the Orcus Labyrinth when Hiyama betrayed him during a monster assault, hurling him into an abyss. Gravely injured and losing his left arm, Hajime confronted near-fatal odds. Consuming monster flesh triggered violent bodily degeneration; drinking "Ambrosia" water then accelerated healing, mutating him into a monster-human hybrid. This transformation whitened his hair, reddened his eyes, etched crimson veins across his skin, increased his height by 10 cm, and forged a muscular build. Psychologically, trauma reshaped his gentle demeanor into ruthless pragmatism—fixated solely on survival and returning to Japan. He discarded moral limits, prepared to eliminate any obstacle, including former classmates.
In the labyrinth's depths, Hajime discovered Yue, a vampire princess imprisoned for 300 years. Liberating her cemented their partnership and interdependence. Together they overcame the dungeon's trials, though Hajime sacrificed his right eye to a hydra. He replaced lost limbs with artifacts: a prosthetic left arm and a "Demon Eye" concealed by an eyepatch. Leveraging Synergist skills and Earth-derived science, he engineered firearms such as the railgun pistol "Donner" and sniper rifle "Schlagen." Consuming monsters bestowed superhuman strength, magic manipulation, and lightning-based powers. Upon uncovering Ehit's manipulation of Tortus, he resolved to collect ancient magics from seven labyrinths to return home, disregarding the world's destiny.
His journey expanded his circle: rabbit-girl Shea Haulia joined after he trained her clan for self-defense; dragon-woman Tio Klarus allied post-defeat, awakening her masochistic inclinations; Kaori and swordswoman Shizuku Yaegashi later integrated into his group. Teacher Aiko Hatayama accompanied them, tasked by Hajime to "remind him of his humanity." Despite his icy exterior, he fiercely guarded these comrades. Bonds with Yue, Shea, and adopted dragon-girl daughter Myu gradually softened his personality, though he retained pragmatic independence—refusing to solve others' issues unless they aligned with his objectives. After securing all ancient magics, he unlocked "Concept Magic" to manipulate reality, forging a "Crystal Key" for interdimensional travel. When Ehit abducted Yue, Hajime's near-apocalyptic fury was restrained by allies, culminating in Ehit's defeat.
Post-conflict, Hajime wed eight women: Yue, Shea, Tio, Kaori, Shizuku, Aiko, dragonkin widow Remia (Myu's mother), and princess Liliana Heiligh. Metamorphosis magic restored his hair and eyes to original black and brown hues, while prosthetics were disguised as natural limbs. Returning to Japan, he managed a jewelry enterprise via alchemy, shielded loved ones from threats, and honored promises. Classmates observed his newfound confidence and leadership, starkly contrasting his past self. Yuka Sonobe persisted as a close confidante with unresolved romantic tension, though she remained outside his harem.
During a class expedition to the fantasy realm Tortus, Hajime and peers were summoned by the deity Ehit. While classmates gained combat abilities, he received the non-combat "Synergist" role, capable of basic alchemy and material transmutation, intensifying his marginalization. His pivotal moment unfolded in the Orcus Labyrinth when Hiyama betrayed him during a monster assault, hurling him into an abyss. Gravely injured and losing his left arm, Hajime confronted near-fatal odds. Consuming monster flesh triggered violent bodily degeneration; drinking "Ambrosia" water then accelerated healing, mutating him into a monster-human hybrid. This transformation whitened his hair, reddened his eyes, etched crimson veins across his skin, increased his height by 10 cm, and forged a muscular build. Psychologically, trauma reshaped his gentle demeanor into ruthless pragmatism—fixated solely on survival and returning to Japan. He discarded moral limits, prepared to eliminate any obstacle, including former classmates.
In the labyrinth's depths, Hajime discovered Yue, a vampire princess imprisoned for 300 years. Liberating her cemented their partnership and interdependence. Together they overcame the dungeon's trials, though Hajime sacrificed his right eye to a hydra. He replaced lost limbs with artifacts: a prosthetic left arm and a "Demon Eye" concealed by an eyepatch. Leveraging Synergist skills and Earth-derived science, he engineered firearms such as the railgun pistol "Donner" and sniper rifle "Schlagen." Consuming monsters bestowed superhuman strength, magic manipulation, and lightning-based powers. Upon uncovering Ehit's manipulation of Tortus, he resolved to collect ancient magics from seven labyrinths to return home, disregarding the world's destiny.
His journey expanded his circle: rabbit-girl Shea Haulia joined after he trained her clan for self-defense; dragon-woman Tio Klarus allied post-defeat, awakening her masochistic inclinations; Kaori and swordswoman Shizuku Yaegashi later integrated into his group. Teacher Aiko Hatayama accompanied them, tasked by Hajime to "remind him of his humanity." Despite his icy exterior, he fiercely guarded these comrades. Bonds with Yue, Shea, and adopted dragon-girl daughter Myu gradually softened his personality, though he retained pragmatic independence—refusing to solve others' issues unless they aligned with his objectives. After securing all ancient magics, he unlocked "Concept Magic" to manipulate reality, forging a "Crystal Key" for interdimensional travel. When Ehit abducted Yue, Hajime's near-apocalyptic fury was restrained by allies, culminating in Ehit's defeat.
Post-conflict, Hajime wed eight women: Yue, Shea, Tio, Kaori, Shizuku, Aiko, dragonkin widow Remia (Myu's mother), and princess Liliana Heiligh. Metamorphosis magic restored his hair and eyes to original black and brown hues, while prosthetics were disguised as natural limbs. Returning to Japan, he managed a jewelry enterprise via alchemy, shielded loved ones from threats, and honored promises. Classmates observed his newfound confidence and leadership, starkly contrasting his past self. Yuka Sonobe persisted as a close confidante with unresolved romantic tension, though she remained outside his harem.