Let's not talk about the 'outlived' yeah? Lets enjoy the present.

He kind of awakened his Incubus powers plus he has half of the Kernel so I'll just have myself believe that would extend his lifespan considerably.
And from how they mentioned demon kings frequent change and passing down of bloodlines, I think they don't live that much longer than humans either. The fluff dad said that their bloodline has had the Kernel for the last 300 years so he's either that old or younger and it got passed down to him (probably latter).