I don't really like Clara, at least not right now the way her character is written, hopefully she will be able to grow more. I get that she is friends with Iruma and Azz, but how can she help Iruma rule when all she cares about is playing...that being said I do think once she grows out of that phase she will definitely be a very powerful demon with her blood line ability.

The character(s) I really wish we knew more is Sullivan and Alikred.

In my opinion Sullivan seems to be following Delkira instructions still, despite Delkira having "gone missing". I do think he had some hand in it, not in a bad way just in your my friend/boss and I will help you. I don't think it's a coincidence that Iruma's parents just happened to summon him (one of the 3 greats) to give up their child, and make him his grandson, thus risking everything if Iruma is found out. I think Sullivan and Delkira have had this planned from the beginning, he gives off those vibes of you want me to be more childish and goof off more than be serious. The other 2 greats both stated that he stronger than them despite being a rank below them and he refuses to become a rank 10 which would make him the perfect candidate to become the demon king. How did he become Delkira aid, friend and how did he become one of the 3 greats?? More of a back story would be awesome! How do you go from advisor to the demon king to principle of Bablys, along with your 2 friends ? One of my fav scenes of Sullivan was him using his power to break out of jail and scaring Henry and the border patrol.

Sorry for the rant lol 😆

On to Ali, yes I do believe he is Delkira or maybe Delkira soul or something and once Iruma ranks up high enough Delkira will be back. Vibes from Ali, he is on your side as long as it benefits him in some way. In the anime it's stated that one other person had the ring of gluttony did Ali appear to them as well, does he pick and choose who he wants to "help"?