One of ARATA MIZUNASHI's Luden creations.
Made using data from Lucil Filarete, a certain someone's memories, and a spirit that had long resided in Svetlana Amou's shop.

Think of her like a Japanese "zashiki-warashi"—a house spirit. She hates Svetlana, but not in a particularly harmful way. She's more of a loud nuisance.

However, after ARATA MIZUNASHI made her his assassin, she was twisted by destructive urges. She now finds joy in hurting people and is an incredibly dangerous entity. Sayaka will face her many times. Hopefully, Svetlana can eventually take her back...