User blog comment:Hitsuji Mamoru/Servant Creation Room 2 : Guess of the Who/@comment-31726296-20170716021510/@comment-31726296-20170717002814

Your close, yet no cigar. Just think what group of people in FGO possess the Projection Magecraft skill? Than ask your self in what doujin dose a person who possess Projection Magecraft, and have Ruby at the same time.

if you are still confuse her story was based off of one the Routes in FSN.

I HOPE THIS HELPs, 😄.