Undercover as a Deliveryman

Ryan Grant, the heir to a legendary martial master, moves in with the Lewis family as their live-in son-in-law while posing as an ordinary nobody. To learn what everyday life is really like, he takes a job as a delivery driver. After he finally completes his training and reaches martial mastery, he rises against the Overlords to protect the nation and wins lasting renown. Yet the Lewis family, who prize money above character, turn their backs on him, while the domineering Sheen family pushes him around without mercy.