read at your own risk

if you already watched season three (ep 79 & 80) then you already know about few things:

1. Yuuri has celebrated his coming of age (16-year-olds were considered adults in Shin Makoku)

2. There was a meeting held in the blood pledge castle between the 10 noble families (while yuuri was still away), as to who would be fit to be the 28th maou. The following candidates were as follows:

anissina von karbelnikoff (nominated by gunter von christ)*hmm...*
cecilla von spitzberg (nominated by stoffel von spitzberg)*huh?
wolfram von bielefeld (nominated by waltorana von bielefeld) *what?!*

It was decided that wolfram would succeed yuuri as a maou.

3. Because of pressure that Wolfram's uncle give him, and because he really wanted Yuuri to rule as the king, he left with a note saying that he's breaking off his engagement with Yuuri. *nande?!*

Before Yuri returned to Shin Makoku at the end of Season 2, the Ten Noble families chooses Wolfram to become the next Demon King. Conflict arises when Yuri returns, and Wolfram is forced to call off their engagement due to Wolfram's proud mazoku uncle. In the end, Yuri becomes the Maoh to defend himself and Wolfram, and proves to the noble family that he is a responsible Maoh. This is later followed by a few individual side stories, such as the episode about bear bees being sold in Shin Makoku, in which later are proven to be fakes; and the episode of Leila's wedding to Antoine, the king of the Francia kingdom. In this episode, Yuri and his companions encounter a group of bandits that have been stealing important swords from different kingdoms, it is later revealed that they have a deeper purpose. The story continues on as Conrad and Murata travel to Big Shimaron to fulfill some somewhat hidden agendas, who are later followed by Yuri and Wolfram. A new character is introduced, the new king of Small Shimaron- Sararegi, who seems to be interested in Yuri. The Original King appears to be well as he appears to Yuri to give him advice, as well as threatened those who oppose Yuri's rule. Finally,Yuri and Wolfram back to their engagement.