Nika

Nika is an Arrancar that was sealed away by Captain Yamamoto around 400 years ago due to her immense power. However, after a scuffle between Gai Nagareboshi and Touma Yamada, she is released from her prison. At first, she is thought to be the main antagonist of "A Certain Unlucky Person" however, after Gunha Teishin makes his appearance and plans known, she quickly becomes one of Gai's most powerful allies.

Appearance
Nika is a young woman, looking twenty years old. She has long, blonde hair that reaches down to her feet; with her bangs hanging down to her breasts, a red bow at the back of her hair, and a barrette holding the rest of her hair into a long ponytail. She has soft blue eyes that are deceptive of her true nature; and sharp canines. She wears a long, flowing pink dress with various patterns on it; as well as long, white gloves that reach up to her elbows. She also wears sandals. She has large breasts, and wide hips.

Personality
Nika is a woman of oddness. When she awoke for the first time in four hundred years, she stated that she was "glad to see that the sky's still blue". However, part of her goofiness is an act: she is cunning, ruthless, and pragmatic. She will go to any length to ensure that she comes out the victor in anything that interests her, even going as far as to shoot someone over a game of Mahjong. Despite this, she is slothful and childish, due to the nature of her upbringing, as noted by Gai to be "erratic in her behaviour...I can't tell if she's just crazy or pure evil." Due to her upbringing, she knows nothing of the world or how to interact with others. After Gai accidently unsealed her, her first act was to level half of Rukongai with a smirk on her face. She mocks Gai's androgynous appearance and teases him, though this extends to several other characters as time passes. As Gai was the first person to physically strike her, despite her "Vectoriales" and Gai's innate lack of spiritual energy, she declared him to be her archenemy. This has had several negative effects on Gai's desire to be normal, as she often shows up to torment him when things go wrong. In a sense, Gai likens her to an "internet troll". Even before she is revealed to be on the side of good, Nika is shown to be a whimsical individual who, although knowing the basics of the modern era, does not seem to know about social norms. Once, she shows up at Gai's school and waves to Gai from the school rear courtyard, luckily for Gai only Naya spots her. After she is revealed to be on the side of good and she reconciles with Gai, she works together with Gai to stop Gunha, she gradually begins to enjoy life and starts to like Gai as more than just a friend.