This is a world that only the strongest gets to rule. The ancient alchemy is about to rip a hole in the universe while the flaming sword of heaven is going to put an end to the cycle of lives. Rulers of thousands of realms are killed by one that has the bloodline of Titan. Qin Nan, the chosen one, who has cultivated an invincible martial art, has embarked on the road to eternity by defeating countless geniuses and dominating the heavens!

At the end of the calendar 2020, the continent of Stern, which has reached the end of civilization due to the exhaustion of magic elements, ushered in the destruction of the continent under the void storm. Ye Xuan, the last god of law in the mainland, unexpectedly awakened in the era of the prosperous magic civilization three thousand years ago and became an ordinary student at the Sith Magic Academy on the border of the Kingdom of Orlando in the northwest of the mainland. In order to save the mainland and prevent the end from coming, Ye Xuan began to explore the mystery of the dark turmoil that led to the depletion of magical elements in the mainland three thousand years ago, to prevent the mainland crisis.

Kinnikuman II Sei takes place several years after the events of the original Kinnikuman. Mantarou Kinniku is the 59th prince of Planet Kinniku and son of the renowned wrestler, King Suguru. Lazy, immature, and cowardly, Mantarou seems to have little in common with his heroic father. When a powerful group calling themselves the dMP threatens the Earth, only someone as powerful as Kinnikuman stands a chance against them. Not knowing the current whereabouts of the King, a plan is formed to have his son Mantarou take up the mantle. The idea of fighting super villains does not sit well with Mantarou, who initially runs away from his duty. He flees to Earth where he encounters Meat, his father’s old trainer. Despite Mantarou's shortcomings, Meat sees King Suguru in him, and believes he can set the prince on the right path. Thus begins Mantarou's journey to better himself and save the world.