it's because leon convinced his family to bond they should cook their own meals and have proper family meals, since the maids were originally cooking and cleaning everything
maybe the attack type invaders that xx's was part of are remnants of the human dragonization project trying to use akabane, while death messiah is the dragonization attempt good guy kiratani made to do good and bring back his son, since the evil one can't destroy it since it's both their son...
My personal theory has been that D was the newborn member of the dragon priestess family before being turned into the collective of footsoldiers instead of being turned into a weapon like the sisters, so D's daddy is yellow keeper?!?!
extension on that theory the dragon executive was created by the newborn dragon priest being turned into an executive rather than a divine tool, and split into footsoldiers when realizing it was a dumb move
i've always been speculating that D and by extension the rest of the footsoldiers are the collective of the unborn/newborn dragon priest since yumeko was talking to a pregnant dragon priestess in a flashback in ch 105