High‑school student and avid gamer Suigin Riku studies at the renowned Shinryou Private Academy, an institution reserved for the privileged and offspring of affluent families. Yet the terms "rich" or "wealthy" do not fit Suigin; he is actually destitute and must juggle multiple part‑time jobs to afford his tuition. While working one of these gigs, he plunges into a pool to rescue his beloved cat, fully knowing he cannot swim. Fortunately, he is rescued by Rei Riku, the striking and popular daughter of a game developer, and he instantly falls for her.
He also becomes intrigued by another girl: a new acquaintance he meets in Dungeon Century, his favorite online RPG. When the game is slated to shut down, he realizes their shared adventures will soon end. The very next day after the closure, he discovers that Rei and this online friend are actually one and the same. Shortly thereafter, Rei presents Suigin with a new title intended to replace Dungeon Century—a tomb‑raiding game called Grave Buster. When Rei is abruptly abducted, Suigin is drawn into Grave Buster to rescue her.
Gin no Guardian chronicles Suigin as he navigates Grave Buster in pursuit of Rei, uncovering the hidden mysteries within the game.
