Asahi Ikusaba, an otaku, finds himself in a new realm after rescuing a child, believing he's gained cheat skills from his beloved games and novels. However, a harsh reality sets in when he faces a formidable monster and realizes he's just an ordinary guy. In a critical moment, he calls upon his adoring sister, Maya, who surprisingly possesses the extraordinary powers he craved. Eager to safeguard her brother, Maya vows to defend him using her newfound strength. United, the devoted siblings strive to return home amidst their extraordinary adventures. Yet, as a menacing army led by the Demon King closes in, it becomes apparent that Maya alone can confront this looming threat.