You guys seem to be thinking too much so Ill say this, the Death God was just giving a "you poor thing dont know what are you getting into getting involved with that guy" pat on the head to the priestess
I mean since the start the guy really fit of demon lord quality, even if we somehow leave out his very questionable morals , his powers to dominate everything sort of fits the bill, hell he even already went and "defeated" the goddess
I feel the poor artist getting the beer bees description and saying fuck this, like it really looks on the design he gave up on trying to make it logical.
Hell, it looks like Spongebob´s marine bear variants