Not really Fluttershy; this being is actually a clone made by SEELE using the Eighth Angel's remains and Fluttershy's DNA in the hope that she would infiltrate the Mane Six and eventually be destroyed, bringing them one step closer to the Covenant with Lilith mentioned in Rebuild of Evangelion.

Befitting this angel, the songs used are "Destiny" and "Fate", the pieces used during the fight with this particular Angel.