Wow, thats the best theory I heard so far. We all know that Tizzy has a plan... somewhere in a book

So, my thought right now, is that Tom and Rupert are in the exact same boat. They are both ancient deities/demons that should have been permanently killed, but somehow reincarnated. I think Tom only stayed human his whole life because of the low mana density on Earth. Maybe if he had lived a few more decades he would have eventually started turning like how Rupert did. I bet if "human" Tom had been taken to the abyss, he would have reformed there whenever he died just like how Rupert did. We also don't know the time difference between Earth and Astlan. Whatever ( cough, Tizzy, cough) caused them to reincarnate could have happened at the same time, Tom might just be older because Earth is a bit faster. This way we don't need any of the completely denied time travel shenanigans, or someone else being the father. This would also explain how a "half-demon" like Rupert is so powerful, he didn't have a demon parent and a human parent, he had a demon parent and a surrogate.

So they could be the same age. Actually it would be hilarious if it turns out Rupert is actually a bit older than Tom.

But, back to my theory. If Tom had lived on Earth longer could he have gathered enough mana to begin transforming into a demon, or was his body truly, purely human?