About to enter junior high school, Karada Iokawa is a cheerful and reliable girl, who hates being treated as a child more than anything. After her parents' deaths, her older brother, Hiro, comes back from studying abroad to take care of her. His ex-girlfriend Shouko Nogami, a composed yet sometimes childish and stubborn young woman, follows him to Japan in order to find out why he left her. Between the two girls, the atmosphere is tense, which eventually leads to Shouko calling Karada childish. Later, Karada stands before a shrine praying to grow up. Little does she know that the shrine wishing stone would grant her wish. As Karada grows older, at the same time, Shouko, who happens to be nearby, finds herself a child once again. With their ages now reversed, Shouko and Karada must come to terms with one another and ultimately themselves.

For the past 13 years, the Nefarious Monster Army have appeared beneath their floating fortress every Sunday to advance their goal of conquering Earth. Luckily, the Dragon Keepers are here to save the day! Having defeated the majority of the monsters during their initial invasion, the heroes now routinely show up to clear away any remnants of resistance. Unbeknownst to the public, however, every fight beyond the first has been a deliberate show put on by both sides: the Dragon Keepers reap the fame and prestige from fighting imaginary enemies, while the surviving weakest monsters, altogether called Dusters, are allowed to live for another day. Sentouin D, a Duster tired of living this life of shame, leaves the fortress in an attempt to overturn his fate. With the unexpected help of the mysterious ranger Yumeko Suzukiri, he discovers the key to defeating the Dragon Keepers lies in their Divine Artifacts—ultimate weapons crucial to the rangers' transformation and unique powers. Teaming up with Suzukiri to infiltrate the garrison of Red Keeper Sousei Akabane, Sentouin D must defy all expectations to save his species from the cruel hands of humans.

As society rises from the ashes of war, cybernetically augmented arena fighters battle for fame and fortune... or die trying. It's the 19th century, and the world has entered the Era of Rebirth, recovering from the devastating flames of war. The sport of mechanical martial arts has galvanized the nations. Cybernetically augmented fighters turn their blood into steam and their bodies into brutal fighting—and killing—machines. Young Levius is one of those arena battlers, hell-bent on winning in order to simply survive.

The second half of second season of Kengan Ashura. The end of the battle is near, and the Kengan Life-or-Death Tournament eagerly awaits its winner.