Watch Kyou kara Maou! 3rd Series Online

Two transfer students, Mitsuhashi Takashi and Itou Shinji, tired of their boring normal life and unpopularity decide to take their arrival at a new school as an opportunity to reinvent their image, and become delinquents! Itou's justice clashing with Mitsuhashi's mischievous ways, they initially antagonize one another but soon become fast friends. The delinquent duo set out on various misadventures to become the greatest delinquents in all Japan!

Life has returned to some form of normalcy after the end of the series, and so His Majesty Yuuri Shibuya travels to oversee how things are going. While doing so, he runs into the king of Small Shimeron--Sararegi. But it seems there may be something more to him than the friendly king he presents himself as. Yuuri go back to Shimaron to relax and meet some friends, when the "king" of Little Shimaron suddenly joins the group and wants the Maou to come to his country. The Original king sends a message to Yuuri's brother and his friend that Yuuri is in trouble. (Source: ANN)

At the end of season 2. Yuuri defeats Shinou, but since Shinou had been defeated, Yuuri and Murata could no longer go to the Shin Makoku. However, because Yuuri had fought and defeated him, his powers had surpassed that of Shinou's, resulting in him being able to rely on his own power to return to Shin Makoku. After the ceremony at the age of 16, Yuuri slowly begins to discover that much has happened while he was away. The ten officials of the noble family have decided to make Wolfram the next Maou, but now that Yuuri has returned and taken back his role as Maou, complications arise when one noble disagrees with Yuuri returning to the throne. In addition, an ancient secret society that threatens the peace of both humans and Mazoku has risen, and a fight for the throne that now leaves the nobles wondering who is the legitimate Maou.