User blog comment:Hitsuji Mamoru/Servant Creation Room 2 : Guess of the Who/@comment-27971189-20170327055247/@comment-4802891-20170327102727

A female Saber (legit?) with fairly high acceptance of magic, no history of riding stuff, the ability to deal extra damage to creatures of "Mystery", a strong Noble Phantasm specifically made to deal with giant creatures and a dreamlike charisma... From her comments, she is fictional and consider herself pretty famous.

Is she a book character (=/= legendary character, folklore character)?