She has an intercom in her room and not at (or near) the front door? Is that common in Japan? We know she has a kitchen and a bathroom at least outside of her room.
And I still don't get the demon/possessed form appearing in the mirror and quickly during the stream while we have that red filter during this whole arc. Is the demon posing as her but using a filter to appear to be the regular Messiah-chan? Still wouldn't explain the blood after taking the head of the doll unless that was a ketchup-themed Shinra-sama.
But I would guess that's Crow-san finally making his appearance then?