It actually depends on the nature of the magic item and how it works. This varies a bit more with religious artifacts than with wizard artifacts.
Well, Tom would of course defend him, because he’s Tom’s treasure.
If you win a prize at a carnival and later someone comes and tries to take it from you, wouldn’t you defend it?
I am sure Tom will want to keep his toy to play with. I certainly would.
So, yes, there are going to be lots of people that want Talarius, for a wide variety of reasons. However, there are also going to be a lot of people (demons) interested in Tom and what he seems to know how to do.