Rosario + Vampire III is a sequel to Rosario + Vampire I and II. It is about twenty years later into the future, the children of original characters are now the stars of the show. The main male character is Kairos Zaraki he is a 9th Grade repeat due fighting and is enrolled at Infernus Academy the form Yokai academy is now an international school for monsters around the if they wish to go there. The main female character and love-interest is Lazuli Viola "Vi" Akashiya the youngest daughter of Tsukune and Moka Akashiya and older half-sister of Nozomi Shirayuki, Ayako Sendo, and Yuzuru (female with male name) Kurono.

Fairy Tale's goal still continues for monster ruling over the world and now the legacy of the former cast and the mysterious Kairos and his split personality Scuro are now in the final battle between Fairy Tale and those who oppose monsters and humans living in peace and the appearance of the organization Tribunal of Miracles is also a concern are they friend or foe?!