Not much to tell since it didn't materialize. Here is what we asked for:
Antidas is a warrior-king type (the only problem is that he isn't very good at). He should speak like a military man - confident, frank, powerful, accustomed to be obeyed.
Gaelius is a politician. Well-set voice, smooth, manipulative, charismatic, accustomed to make a strong effect on weaker minds. When he says "today I rule this, tomorrow I will rule that", it's not a boast or a threat. He says it matter-of-factly, as if trying to make you to understand why a guy like him, a guy who has it all, will never do anything of that sort (use 'magic'). He just doesn't need this ♥♥♥♥.
Meru is a religious fanatic. Not in a 2-bit way, but more like Cromwell - a man who used his faith and convictions with great effect, doing the unthinkable (executing a king). He is soft-spoken and sounds like a kind uncle, but he is anything but. Ideally, I'd like his voice change, shifting from a softer intro to more menacing when he says "who'd raise a hand..."
Lorenza - clever, manipulative, disdainful. The difference between her and Gaelius, for example, is that he was given everything and had to manipulate others to keep what he was given and grow it, whereas Lorenza had to do it to survive and stay one step ahead of the competition and assassins.
The demon is a construct, but he's fairly sarcastic and arrogant. He's toying with you and enjoying it. Think of our attempts to give personality and human voice to iphones (Siri and such). Similarly, the magus who crafted the construct wouldn't want him to sound robotic. Its inhumanity should be in rapidly shifting intonations. For example:
“Destroy. Kill. Render inanimate. Do you have any preferences? I am an expert in such matters, so if there is some sort of demise you would enjoy more, I am happy to oblige. I am familiar with more than a thousand ways to end a human life, and I am sure that I am capable of accommodating even the most exotic requests.“
...
“Since it’s unlikely that you can understand the concept of a silicon-based life form, consider me a “stone guardian“. I was created by the master of this tower, though he appears to be long gone. Such is the nature of flesh - it doesn't last. Stone, on the other hand, lasts forever. A gift and a curse at the same time, really."
"destroy, kill, render..." - unemotional, list-like, like explaining the meaning of a word to a dumb person
"do you have any preference" - helpful, eager to be of service
"I'm an expert..." - arrogant
"if there is some sort of demise..." - helpful again
"such is the nature of flesh..." - fake sadness
"stone, on the other hand..." - fake humility changing to pride