That could mean loads of things depending on what the character intended.
It could mean:
- Paul is mine, so nobody else is allowed to care as much as me if he dies.
- If Paul dies, remember that I will be very distraught as I more or less own him.
- I'm in a vulnerable position, because I've invested a lot of emotional energy in Paul.
It could also mean:
- Having not personally taken steps to protect Paul, I fear that he might be dead.
Undoubtedly it could mean plenty of other things, it's a very cryptic, even metaphysical expression. If you could give more context that would be great.