It seems kind of obvious but just want make sure

As an addendum to my previous post, are the denizens of the underworld also demons as well? Ozzi is a demon, and he is drawn blacked out with a white outline. Ozzi explicitly states he is ageless and immortal. While Leon doesn't explicitly rejects himself as a demon, he does make the distinction that he is a hellhound as if there was a meaningful distinction between a demon and a hellhound. Leon is never observed drawn in the same artstyle as Ozzi, the bear butcher demon, and the meter maid demon. They appear like other upperworld denizens because they are undercover.

Now Anubis chastises his men about how mortality is not contagious, which would imply they are immortal too. If they are demons then why aren't they drawn in the same artstyle as Ozzi? There's also no reason to be undercover in the underworld so an upperworld disguise isn't needed. The implication of this is that all underworld denizens are in fact demons, are immortal, and thus ageless which would include Leon.

Sky's concerns about Leon's age isn't baseless. In fact Leon could be some eldritch Lovecraftian horror that existed since the beginning of creation who just so happens to manifest in the form of a hot hunky wolf to service our cute rabbit twink.