Takumi Hirooka, a 20-year-old exhausted salary worker, collapses at home after treating his beloved dog Leo to a convenience store snack. He awakens in an unfamiliar forest—only to discover Leo has transformed into a colossal Silver Fenrir, one of the world's most formidable monsters. When Leo effortlessly defeats the creatures prowling the woodland, Takumi realizes this is no dream. He meets Claire, a noblewoman who recognizes Leo's legendary status and invites them both to her grand mansion. As Takumi adjusts to his new reality in this otherworld, he uncovers an unexpected ability: Weed Cultivation—a seemingly useless gift that may hold hidden potential. Now living under Claire's roof, Takumi navigates this fantasy realm with Leo standing guard as his unstoppable protector. Armed with his mysterious power and accompanied by the mightiest of beasts, Takumi embarks on a new chapter far from the draining corporate grind—one where a simple man, his legendary companion, and a cultivation gift forge an unlikely adventure together.