Yuika

Background
Yuika was reincarnated as a 『Little Oni-Kin (Goblin)』. She resides in lower layer of Labyrinth in Selbira City. She's afraid of people after having through some terrible things, because of that she's remain hidden in the space domain she created herself. Her space domain is powerful, can't be detected by Clairvoyance magic and Satou's Map, even God won't be able to peek inside.

Yuika has 『Multiplepersonality』, when she experiences painful things, she will leave the memory in the old personality and then change into a newly created personality. The old personality is like the spirit on your back, they can only be a spectator. When the main Yuika personality sleeps, it seems they can posses her and resurface.

Despite her appearance as a goblin. She isn't actually a demon lord. She was once called a demon lord by

Yuika's level decreased by 30 whenever she creates a new main personality. Her skills are lost along with it too. Their skill and level can go back if they get hold of the main body from the main personality, but it seems the level can only go back by 20% of the main personality at most. Moreover, there's also some rule about affinity. Apparently not all the versions of Yuika have access to all the unique skills insider her body.

The Yuika are named by Satou in the order he meets them, not by their true age or order of creation She doesn't have any normal skill, her level is 50. She is the youngest incarnation shown. She has access to the skills [Create my Garden], [Infinite Chain], [Mana Spring], [Mana Loop] and [Divine Sight] Has hand-to-hand combat-related skills, her level is 55. She has access to the [Guardian] and [Peerless Strong Arm] The first generation, a chuunibyou personality, called herself 『Jet Black Beauty Dark La Princesse』Foilnis La Belle Fille. Has magic warrior related skills, her level is 52.
 * Yuika No.1:
 * Yuika No.2:
 * Yuika No.3:
 * White Oni Sovereign. The incarnation Satou has stated to have created by accident when he defeated Yuika No.1. It is capable of using all 13 Unique skills.

Appearance
A beautiful girl with slender delicate body, white transparent skin, and silk-like lustrous straight violet hair that extends to the floor. Her ears is slightly pointed, resemble an elf's. There is also two small horns on her forehead near the temples of her head. Her eyes have violet-colored pupil, the color changed when she change personality.

Labyrinth City
Satou, as Kuro, visits Ban Hellsing in the lower layer of Labirynth in Selbira City. While doing underground tour, he stop by at Yuika's place. Yuika looks happy briefly when she notices Satou, but then maybe because she knows Satou true identity she starts to attack him repeatedly. After parries her attack, Satou strike Yuika to make her faint. But then Yuika's new personality emerges. Satou's strike was stopped by a hard magic wall, but knowing its weakness, by using magic power in his strike Satou successfully make her faint.

Satou catches the fallen Yuika, but she that's supposedly fainted suddenly open her eyes. Her personality changed, but not only that, half of her skill composition also changed to hand-to-hand combat-related skills. After evaded her attacks, Satou takes some distances of her. Yuika who become embarrassed after knew that her clothes has fallen, stops her movement. Satou gives her a mantle to cover her body, but then another personality emerge, Yuika No.3, a chuunibyou personality called herself 『Jet Black Beauty Dark La Princesse』. Her hand-to-hand combat skills also become that of magic warrior.

Yuika No.3 can see Satou's true identity using her unique skill. She then asks Satou his objective. After confirms the truth that Satou despite has Hero title doesn't have any ill intention towards her and only want to greet the woman who came from the same 『Former』 world as him, she at a loss for words. Later they reconciled somehow. After have some meal together and become friend, Satou give Yuika No.3 a new chuuni name, White Oni Sovereign.

Kingdom Conference
Satou bring Shin that afflicted with [Miasma Poisoning] after his transformation to Demon Lord to Ban Hellsing castle. Satou seeks help to cure Shin after his efforts was in vain. After Yuika with her vast knowledge notify tell Satou several way to solve the problem, Satou sucessfully cure Shin.

Skills
Her skill composition change when the personality change.

She has 13 unique skills, some of them are:
 * Create My Garden (Can create plant life anywhere anytime)
 * Infinite Chain (A spell can be re-cast indefinitely instantly after casting it just once)
 * Mana Loop (perfect control of Mana in the surroundings)
 * Mana Spring (creates a well of free Mana)
 * Automatic Defense (Guardian) (automatic defensive barriers are deployed when attacks are near)
 * Peerless Strong Arm (nothing can be physically stronger)
 * Divine Sight (nothing can be disguised)

Equipment
Given to her by Satou for her assistance with making a barrier.
 * Emerald Green Wand (made from World Tree Branch)

Trivia

 * When Satou asked Yuika what she want, she told him that she wants Normal sushi roll.

Quotes

 * "Kukukukuku, ...Hahaha, Haaahhahhahahaha. I am the descendant of the oppressed darkness, the miko demon of the sixth heaven, the last noble of Oni-kin. My name is Foilnis La Belle Fille! Those who fear and honor me call me as the 『Jet Black Beauty Dark La Princesse』!"