Hmm...I just had a sad thought. If something were to ever happen to Crinitus, I'd have a Castlevania situation on my hands. Tyeson may not be a vampire but he's as if not more powerful than Dracula, as well as being old enough to have little apathy left for humanity.
But unlike Alucard, Bellus would probably help his father destroy humanity. I think it would be Laetitia and Mitis that would team up to stop their father and brother from destroying the world.
Laetitia herself would be very destraught after inevitably killing them, as a pacifist and may die herself from grief, like from a broken heart or something.
Thus leaving Mitis all alone to mourn his family and restart the cycle, as the youngest Moonshifter is very much like his father, well how his father is before all the bad stuff happened.
I think in the fall out, Mitis will probably leave humanity itself behind and serve his family's Goddess, who Tyeson was once champion to and Mitis would retake the title of champion, living the rest of eternity lost to the world and under Her full thrall, and living the life that Tyeson fought so hard to keep his children and brother from living.