Stray Servant

A heroine candidate that vanished without a trace during the plotting stage.
She was conceived of as an “abandoned puppy” type heroine, who killed her Master and went on a rampage.
As a Servant of the shield, she was going to be a rival to Saber, the Servant of the sword, but…
Just like Gilgamesh, she would have been a Servant that had remained behind after the previous Grail War. Unfortunately, though, she had to be cut for the sake of keeping things manageable for the player.
After all, around this point, the plot itself was starting to stray. Not only Rider, but even Caster was a potential heroine candidate. It was terrifyingly chaotic.
Hmm? Fuji-nee? I don’t know what you’re talking about, Fuji-nee never had a main route even during the plotting stage.

Fate/side material: Fate Encyclopedia