User blog comment:Stbk22/Possible Power up's/Techniques for then new group DxD/@comment-1359322-20141228030353/@comment-1359322-20150619160558

Well from this quote

"She overcame that by becoming a Devil, and changed it to her own powers. That was Tsubaki-senpai’s Sacred Gear, [Mirror Alice]."

I wonder if there's the possibility that maybe Mirror Alice actually has multiple ability and can change depending on Tsubaki.