1. WHY DOES MEPHISTO HAVE A BOTW/TOTK ZELDA BODY PILLOW (based)
2. Did we ever get any clarification on what exactly is going on with Shiemi? What exactly she is and her relationship to this family (what the hell is a saio) I vaguely remember rereading and waiting for the story to explain but I don't remember anything (other than her making Amimon submit to her?????)
Saio is the title of the person that inherits the powers of Shemihaza.
Shiemi is the granddaughter of the last Saio, her grandma was the last "avatar" of Shemihaza, but because of the complex manner that the power of such a being works with genetics, the power jumped her mother.
And there is a diluting of the power as generations go on, as they become more and more human.
Truth be told the details are foggy in my mind now, there are a lot of details missing in my explanation, especially about who Shemihaza is/was and the relation with the powers that exist in this world, I need to reread.
And like you said... Mephisto is based... and a prick.