Thank you for sharing these illustrations with us. :)We still don't know what SH stands for?Do you know what happens in the book?
There was an excerpt from the afterword about it on the Dengeki website, but I think I'll have to read the whole thing before I can give a confident answer!
Isn't his name Mizuchi Yahiro? On the Dengeki website it says 三頭池八尋（みずちやひろ）
you are righti think read it wrong the first time and it stuckthank you so muchi'm so sorryi will edit and make an announcementthank you for bringing it up!
Mikado red eyes?