elfnein
CV Kuno Misaki
Elfnein, a character who offers aid to the protagonists to be able to fight and stop Carol Malus Dienheim. She is a homunculus created by Carol and appears as a young girl who looks similar to Carol. She actually has no real gender though, as she lacks genitals.
By the end of the third season, while being on the verge of death she merges into the body of Carol Malus Dienheim who at the time is also dying due to damage to her mind. Because Carols mind was almost gone her merged form is predominantly Elfnein. The new Elfnein has carols hair colour (light blonde) rather than Elfneins (greenish blonde) and presumably has genitals.