A man wakes up in the body of Liar, the false hero from his favorite video game, Guilty Sin. In the game’s original story, this character is a minor antagonist whose only purpose is to be defeated by the true hero. However, armed with complete knowledge of the game’s events, future dangers, and hidden secrets, the reincarnated protagonist decides to use his new life for a comfortable existence as an adventurer, leveraging his foresight to avoid trouble and live peacefully.

His plans change drastically when he encounters Artan, the game’s tragic heroine. In every route of Guilty Sin, Artan is doomed to a miserable fate, surrounded by betrayal and death, never finding happiness. Moved by her situation and his own affection for the character, Liar resolves to defy the game’s script. He decides to use his role as the fake hero to get close to her and alter her destiny, aiming to guide her toward a proper, happy ending.

The story takes place in a fantasy world governed by the logic and events of the game Guilty Sin. The main characters include Liar, whose name reflects his constant deception as he pretends to be something he is not, and Artan, whose trust he must earn against the backdrop of a narrative that seems determined to break her. The central conflict emerges as Liar’s actions begin to create unforeseen changes. The game’s world pushes back against his alterations, throwing new challenges and death routes at Artan that he did not anticipate.

Notable narrative arcs involve Liar using his knowledge to save Artan from her initial, well-known tragic endings, only to realize that his interference has created even more dangerous scenarios. He must constantly lie about his origins and motives, weaving a complex web of deception to protect her while hunting for a way to permanently break the cycle of tragedy. The central question becomes whether a fake hero, through sheer will and cleverness, can succeed where the true hero failed and change the fundamental nature of the game itself.