[question] difference

What is the true difference between us demons in a physical form and those demons that are in true form?

Right now you're human. So you're physical in nature and are limited by biology, physics, etc. A non-incarnated demon is (of the ones I've met) energetic in nature and thus *not* bound by the scientific laws that govern physical beings.

As a human being you're subject to your biology and the physical laws that come with it. That's the major difference.

you are human, they aren't.

the difference? a human body. thus you are demon-kin, not demon.

They all summed it up right ^_^

I think the OP was refering to the form that some demons are said to have that is... "semi-physical". Not to demon-kin.

I am not (AFAIK) a demon, so I don't know the truth to "semi-physical" forms...

In the same sense, demons that had physical/semi-physical forms could have reincarnated as human in much the same way as a therian had a physical animal form before, or dragonkin did.

Demons who had no physical form before are essentially being "shoved" into this body, whereas demons with a physical form have had their "core energy" shoved into this body now, with either a part of the core remaining in the other body, or the body being empty or destroyed or dead, etc.