Doragon
You can make it so that Aknologia and Irene have a son, and it turned out to be Zeref. It would be interesting to see what happens.
Idiot, here I show you the evolutionary paths of a demon. -> Lesser demon -> Greater demon -> arch demon -> Demon peer -> Devil lord The primordial at the time of being summoned are in Arch demon and Noir when he was summoned and named evolved into a Demon peer. To evolve to a Devil lord you need to have a name, a body and be at the level of a True demon lord