–As for 1st Generation Demons. Very interesting question. The only person I can think of to ask about that is Lillith, and I’m not sure I’d live through the question once it became clear that I was implying she was THAT old. (even though she is)
If Tom’s link was broken, he would be free until someone else found out his true name and summoned him and rebound him (or tried to).
This is basically what Verigas did. He found the name of a demon who’s master(s) were long dead written in a book and summoned and re-bound him.
As for the spell, there is only one person I can think of who knows enough wizardry, and who knows the truth about demons that could try to create that spell. Or tell you what the “problems with it would be.” However, he’s a bit preoccupied by having his plans thwarted by Lenamare and his demon. He’s also not the most even tempered person…
I suppose you could ask, was he a wizard who became a demon or a demon who became a wizard? I, Tizzy, had assumed he was a demon that learned wizardry, but…I could be wrong.