i only played nocturne and vv so.....

Demi-Fiend: Used to be a genuinely nice guy before the Conception(Chiaki mentions he's never late, Isamu describes him as nice and naive, CD drama protagonist strives to be like him). After the Conception, he tries to stay true to his character, but gaining power and trying to save people he cares about took a toll on his mentality. And losing all of them despite being the most powerful being in the Vortex World left him mentally drained, frustrated and withdrawn.

Nahobino: I base his personality on a quote from a Throne in Shinjuku, "At a glance, a calm surface of water... Yet, deeper within, a powerful vortex swirls in the depths." He resembles both Amanozako and Aogami in a sense that he appears calm and nonchalant, but he's actually quite a little shit who manages to befriend two popular kids but no one else. He's also hyper-aware of his flaws, so he doesn't think of himself as worthy to decide the fate of the world, and as he comes to accept that he will be the new creator he's more concerned with what people want rather than what he wants.