Saraswati Meltout

Benzaiten’s Five-String Biwa.
This is an anti-mind Noble Phantasm given to the Alter Egos by BB.
While anti-mind, in the cyber world it effectively functions as an anti-city or anti-world Noble Phantasm.
This Biwa was made from the Goddess Benzaiten, who is one of the Seven Deities of Fortune, also regarded to be the same as Ugajin or the three Munakata Goddesses.
The Biwa creates a vortex of power that gathers and releases water, and can swallow up all things.
This Noble Phantasm was not meant to be used in combat. It was meant to be used against the sphere of a civilization that has advanced to a certain level.
Meltlilith’s honey doesn’t just melt a person’s body; it also sweetly melts their mind. This Noble Phantasm melts away all the common sense and morality from a community, and unifies the melted pool of people as a single-body colony.
Trampling over and absorbing those whose bodies, minds, and society have been reduced to slime is the true power of this Noble Phantasm.
Considering the massive effect and damage to non-combatants in the area this Noble Phantasm is used, one can see how ill-natured Meltlilith really is.
The original concept for this Noble Phantasm was a vortex of water that sucked the enemy in and made them unable to move. Meltlilith would then thoroughly kick the crap out of the immobile victim, finishing with both the victim and her climaxing.1
So of course, it was axed. Even the god of art couldn’t win against the code of ethics…

Translator's Notes
  1. ^ Think S&M.
Fate/EXTRA Material: Encyclopedia of Fate/EXTRA