Is it coincidence, that a lot of main protagonists have a dark side? or an evil form, counterpart or something like that?
Naruto, Ichigo, Meliodas, Asta, Natsu, Shiki, Goku, Inuyasha, Yugi, Jaden, Gon etc.
But I like it. Therefore I hope that Asta will be the final villain. :)
And I hope his Name is Astaroth, also from his Devil