Claude Grey has spent his life believing that strength is the only reliable way to protect himself and the people he cares about. Living with his father near the forest, he trains every day while attending a Hero academy and constantly struggles against stronger students, especially Samuel Leon. Everything changes when Claude enters a Tangent and encounters Fenrir, the legendary god of wolves. After surviving the experience, Claude is Reborn and receives the Beast Tamer class, giving him a completely different path from the one he expected. From there, Claude's journey becomes increasingly dangerous. He discovers new abilities, develops a powerful bond with Frosty, enters deeper Tangents and encounters creatures and enemies that challenge both his body and his beliefs. His relationship with Ursula also grows as they experience battles, loss and terrifying transformations together. As Claude becomes stronger, he learns that the world is far more complicated than the conflict between humans and monsters. Ancient powers, Lupine factions, Vampires and figures connected to his own past begin to surface. His father's death, the mystery surrounding Claude's origins and the existence of Remus and the Lupines of Romulus gradually become connected. By the end, Claude is no longer simply a student trying to become a Hero. His transformation forces him to question what he is, what he wants to protect and how far he is willing to go for the people he considers his own.