Rounin is the story of an elite group of warriors who live in a place called Lumeria.
The Rounin are tasked to protect the city and its inhabitants against the threats of Helion, the City of Death. Each Rounin specialiszes in a martial arts discipline, and is commanded by the master Rounin, the leader of Lumeria.
While battling their enemies, the Rounin strive to adhere to their tenets – one being they cannot fall in love with each other.
The show centers around the quest of a young Ronin warrior, Mythos, as he tries to piece together his past to unlock his true identity.