Ren Tanaka, an introvert isekai'd as a Level 1 Sage, hides a divine glitch: the Primordial Codex, granting him mastery of all magic and spell creation. Seeking peace, he joins the Adventurer’s Guild, but is forced into a party. His "support" spells—invented on the spot—accidentally unravel ancient curses, rewrite local physics, and baffle both allies and gods. As the Demon King rises, Ren must choose: preserve his quiet life or embrace his title as the Archivist of All Magic, whose mere presence rewrites the world's rules.