Yeah, she created him. And since she's fighting the King of Kegare, which is inside Magano somewhere (right?) she couldn't let him out of Magano so he had to be left in there until some exorcist found him. I think that's about right.
Things are finishing up. Sakanashi finally died. We got a full backstory between Chinu and Sakanashi (this author.. seriously.. really love to write tragic romance story huh)
Yuto took over Benio's body and looks like we are heading to final battle.
Many has called it that the ending will be Yuto remaining in Magano just so Benio can live in human world.
