Thanks for listening to my suggestion even though this story focuses on the relationship of Mairō, Kyū, and Mahiro.
Honestly, this story has a lot of potential and if you play your cards right in the way you write it and create the worldbuilding, you could do something amazing (at least in my humble opinion).
I like that the mother is initially cast as a "villain" from Mairō's point of view since for him, she and Mahiro are one of the main causes that he cannot live freely with Kyū, but when he begins to open up to Mahiro and open up his heart, he also begins to see things more clearly realizing that the mother is as much a victim of the situation as he is only that she doesn´t have her "Kyū" to cope with it (Of course all this is headcanon, if you decide to carry the story or relations to another address, I would love it anyway).
I have a question about worldbuilding: Will the wars be like Nobunaga (Basically region vs region) or country vs country or humans vs demons?
I really love fantasy worlds, so I love that Kyū is a demon<3.