Nika

Nika is an Arrancar that was sealed away by Captain Yamamoto a few decades 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.

Recent History
First Release- Beginnings

Powers and Abilities
Nika is a highly skilled warrior and a tremendously deadly opponent. Due to her Resurrección, "Vectoriales" she has only ever lost twice. Vectoriales creates a thin field of reiatsu around Nika, which allows her to modify the vector values of anything she touches. Furthermore, this ability is automatic, so opposing kido and projectiles will be reflected. However, her physical constitution is rather poor, and it is due to this that Gai Nagareboshi, a person with no innate spiritual ability whatsoever, was able to think of a clever strategy to negate her Vectoriales and defeat her. Vectoriales allows Nika to move at the speed of light and punch with the force of two thousand tons. At night she is almost invulnerable, and her power is at its peak during the full moon. During the night, she becomes indestructible. She can not only regenerate most wounds rapidly, but even re-form her body completely after being bisected by Gai's wings, even though it took the majority of her power to do so.

Master Swordsmanship Specialist: Though she rarely engages in it, Nika appears to be highly skilled in swordsmanship.

Master Hand-to-Hand Combatant: Nika has shown to rely mostly on hand-to-hand combat, rarely drawing her sword at all. Like Ulquiorra, Nika also seems to prefer applying an "off-the-ground" method of combat, often being seen attacking opponents from aerial standpoints, such as when she jumped upwards with a Sonído in an attempt to catch Gai off guard.

Sonído Master: One of Nika's more noticeable traits is her tremendously skillful speed. She has demonstrated the ability to catch up with Gai after kicking him from a tower in a few moments. She has also shown the ability to skillfully keep up with Gai's Bankai speed. Nika moves at an excessively fast speed in combat, so fast that Gai found it hard to even discern her movements at first.

Cero: Nika has been shown shooting Cero from her fingers with excessively destructive power. Her Cero can be charged and fired relatively fast and is a pink color instead of red, which is the most common color of a Cero. The force of the blast is powerful enough to send an opponent hurtling long distances, effectively destroying any obstacle in its path at great range. She is shown able to fire it from either hand.

Bala: This technique hardens the user's spiritual pressure and fires it like a bullet from their fist. Nika has a pink Bala. Nika's Bala is powerful enough to blast a huge hole into two unseated Shinigami.

Enhanced Hierro (鋼皮（イエロ）, iero; Spanish for "Iron", Japanese for "Steel Skin"): refers to the hardened skin of the Arrancar, which is a result of their compressed spiritual power. While not openly stated, it has been seen repeatedly that Nika's skin is highly durable even by Arrancar standards. She can deflect attacks of similar power barehanded. She is able to fight Gai without unsheathing her sword, rendering Gai defenseless with two attacks and not sustaining injuries of any kind.

Enhanced Pesquisa: The Arrancar ability to sense spiritual energy. While any Arrancar can learn it, Nika has shown impressive skill with it. From a single glance at her opponent, Nika can immediately determine how powerful her opponent is. She is also able to comprehend the flow and concentration of the person's energy as shown from her ability to instantly notice Gai's energy is fluctuating constantly.

Enhanced Strength: Nika has proven to be deceptively mighty for her build. She has also shown the ability to kick Gai a tremendous distance with one strong kick.

High-Speed Regeneration: Despite having great attack power, speed, and durability, Nika's greatest strength lies in his regenerative power. This is displayed once more in her battle against Gai's Bankai Form where she regenerates the arm that was torn off. Nika states that it is her greatest power, one which most Arrancar give up in return for greater strength. She explains that she can quickly regenerate any part of her body except for her brain and internal organs. However, this power also requires that she had sufficient spiritual energy.

Immense Spiritual Power: Her spiritual power is immensely high. During her first meeting with Gai, she compared her levels to that of Gai, a Shinigami with exceedingly high spiritual energy, and she comments that the Shinigami's energy at its peak is higher than her own but fluctuates.

Garganta (黒腔（ガルガンタ）, garuganta; Spanish for "Throat", Japanese for "Black Cavity"): Garganta is how Arrancar move to and from Hueco Mundo. Nika has the ability to use the technique. It literally tears open the dimensional fabric separating the worlds, revealing a tunnel of whirling, torrential energy that must be focused and solidified to create a discernible pathway.

Zanpakuto
Vectoriales (Spanish for Vector) is the name of Nika's Zanpakuto. It takes the form of a regular katana. Resurrección Special Ability: She gains even greater physical abilities in this form. Nika also has theability to enter a second released form, called Resurrección Segunda Etapa. Nika creates a thin field of reiatsu around herself, which allows her to modify the vector values of anything she touches. However, "controlling" something with vectors requires very difficult calculations, and one could exploit that to render Nika's moves useless.
 * Resurrección: Its release command is "Control". Vectoriales unleashes a pink burst of spiritual energy that falls around Nika as pink rain.
 * Redirection: She can change the vector values of anything by touch. Furthermore, this ability is automatic, so projectiles like bullets, explosives, or kido have no effect on her, as they will be redirected. However, one can hit Nika by pulling back their attack right before it is redirected by Nika's field, because Nika's redirection field simply changes the direction of the vector towards its opposite, as such anything that is coming towards Nika will be redirected back in the opposite direction.
 * Earth Stomp: Using the vectors behind her feet, she causes a little explosion made of earth and rocks to attack her opponents. She can also use this to propel herself forward at the speed of light, or cause small tremors.
 * Vector Shooting: By touching an object, she can extend the influence of her ability to other objects in contact with it. This way allows her to indirectly change the vectors and turn the objects into projectiles.
 * Wind Control: She can re-vector the surrounding winds and force them to congregate at a single point creating an extremely high velocity wind, but it had flaws like when the wind is moving in an abnormal direction or when her vector calculations are disturbed by sound. Nika can also re-vector the surrounding winds to create a powerful vaccum cut of air, or razor wind.
 * Plasma Storm: She can even create plasma by further compressing the hot air at high speeds in a single point. At that point, the plasma will fan out into several bolts that shoot at the target. Nika could destroy Hitsugaya's ice creations, though she could not stop his ultimate attack.
 * Absolute Zero Blast: Nika can create absolute zero wind by further compressing the cold air at high speeds at a single point. At that point, she could unleash a powerful freezing blast at her target. Yamamoto's Bankai could overpower this attack.
 * Kinetic Blast: Nika takes control of the planet's rotational vectors and transfers an enormous amount of that energy into one attack. This attack used up so much of the planets rotational energy that it slowed down the the earth's rotation by about 5 minutes.
 * Flight: By colliding hot and cold air around her she can create 4 high-powered tornadoes behind her to allow her to fly.
 * Destruction: Nika places force vectors on all of her opponent's organs in different directions.
 * Reverse Engineering: Nika has stated that as long as she has experienced it, she can analyze forces unknown to her as long as her body has been in contact with it, by following the vectors that have been applied.