The reasons why kena soga and akuto sai are perfect to become a couple of this anime:
1. The taube hairpin shows the proof that they have connections to each other.
2. They have met when they're kids and they met again which means that theyre meant to be together :")
3. They have different characteristics. Opposites attract ya know ;)
4. With kena soga, akuto sai's role as a demon king is getting stronger because of the fact that he's always there to protect kena soga.
5. I have read in some sites that the word "daimao" in the Titel is referring to kena soga.
6. Look at the ending theme, there...