Nnoitra is a very tall man with a thin and lanky body. His face is frequently set in a huge smile which reveals his upper teeth. His black hair hangs past his shoulders, concealing the left side of his face and a large white eyepatch with one exposed dark gray eye. The eyepatch hides his mask fragments, consisting of a small set of jawbones and teeth surrounding his Hollow hole. The tattoo signifying his rank as Quinto Espada is located on his tongue. His clothing consists of a modified Arrancar jacket with an overblown spoon-like hood and an opening starting at the neckline, showing most of his midsection, and closing at his waist. He wears the standard hakama, but the ends of his pant legs close inside extended and curved boots.
Personality-wise, Nnoitra is extremely rude, ill-mannered and lecherous, accented by his snake-like eyes and perverted attitude towards Orihime, rudely referring to her as "pet-sama". He even went as far to ask Ulquiorra Cifer how well he "disciplined" her. He is an extremely foul-mouthed man, and is also a firm believer in male chauvinism and openly insults (and regularly attacked) the former Tercera Espada, though it's unknown if he holds the same grudge toward Tier Harribel. His overall goal is to prove himself to be the absolute strongest of the Espada, not wishing to waste his time killing those he dubs "weak". However, he has no qualms attacking stronger opponents who are already injured, a trait both Ichigo Kurosaki and Grimmjow Jaegerjaquez berate him for. He also loathes looking weak, and thus, will refuse all forms of assistance offered to him during an ongoing battle, striking his lone Fracción, Tesra Lindocruz, for running over to his side (and releasing Orihime Inoue in the process) after Nnoitra was blasted by Nelliel's Cero Doble. He does, however, have at least some amount of concern for his sole Fracción's well-being, having attempted to warn Tesra to withdraw from battle after he determined via his Pesquisa that Kenpachi Zaraki was stronger than he had initially anticipated.
One of Nnoitra's most notable characteristics is his insatiable bloodlust and hunger for battle. Nnoitra's idea of a fulfilling end to his life would be to die on his own two feet while drowning on his own blood before he even touches the ground. Because fighting is his way of life, he continually strives to be stronger, and he considers himself indebted to Aizen for allowing him to exceed his natural fighting limits. To appease his craving for a good fight, he even defies a direct order from Aizen to patiently lie in wait for Ichigo Kurosaki and his friends when they try to infiltrate Las Noches in a bid to free Orihime Inoue.
In his later moments during his battle with Kenpachi Zaraki, he begins to show signs of weakness and desperation, and becomes increasingly frustrated over his inability to overcome the powerful captain. This stems from an inferiority complex he developed while serving as 8th Espada, due to his apparent inability to beat his opponents. Whenever his opponents refuse to kill him during a battle, particularly Kenpachi and Nelliel, Nnoitora takes it as a direct affront to his pride, because in his mind, neither Nelliel nor Kenpachi seem to think of him as their equal or superior, proving he wishes to be treated as equally as every other opponent he has treated. Ironically, he treated virtually every one of his opponents the same way, unfairly and through dishonorable methods. He also does not hesitate to use any means - even unfair ones - in order to prove his superiority on the battlefield.
Master Swordsman Specialist: Nnoitra is highly masterful with his unique Zanpakutō. He uses his skill to become somewhat of a savage brute, as the lack of true law in Hueco Mundo allowed him plenty of opportunity to engage in battle against Hollows and other Arrancar alike. He effortlessly wields his large Zanpakutō with ease, taking advantage of its unique shape to maximize his attacks. He is highly capable of using it as a ranged projectile as well as he does with it in hand. He is commonly seen using brute strength to hack down an enemy's defense. Defensively, at least in terms of his released form, he uses one pair of arms as defense, abruptly switching which arms would defend. His other two arms would serve to attack the opponent. This results in unpredictability in Nnoitra's fighting pattern, and can easily overwhelm and fight off an aggressive opponent.
Expert Hand-to-Hand Combatant: Nnoitra possesses at least some skill in hand-to-hand fighting, as shown when he delivered a punch and a kick to Ichigo's face before attempting to break the bones in his wrist. Mimicking the fighting style of Kenpachi, Nnoitra also utilizes grabs, slams, and holds, as shown when he forced Ichigo's face into the ground.
Enhanced Hierro: Nnoitra holds the self-proclaimed title for the strongest Hierro of all Arrancar (including the Espada past and present) in Hueco Mundo, allowing him to withstand almost any attack with no sign of injury. His Hierro is so strong, that it allowed him to grab Ichigo's Bankai: Tensa Zangetsu, without sustaining any serious damage from the blade's sharp edge. However, Kenpachi Zaraki eventually found the necessary requirements to harm him after a brief trial-and-error duel; sharpening his Reiatsu in order to cut through Nnoitra's Hierro. This shows that while his Hierro is strong, all the opponent has to do in order to overcome it is "adapt" to its density with their own Reiatsu.
Enhanced Strength: Despite his thin and fragile appearance, Nnoitra is frighteningly strong and can effortlessly put a lot of destructive power behind his large Zanpakutō with devastating results. Just by spinning his Zanpakutō by the chain-link he can create whirlwinds to damage his opponents.
Indice Radar (Mark Radar): Nnoitra is capable of using an advanced version of Pesquisa. While the technique normally works by entering a meditative state and functioning like sonar, all Nnoitra needs to do is put his hand to a grounded surface. His Pesquisa is even able to gauge the amount of spiritual power an enemy has, which he uses to identify potentially strong opponents.
Cero: His Cero attacks are uniquely golden, and are fired from the tip of his tongue as opposed to using his hands or fingers like most other Arrancar do. However, the strength of his Cero is virtually unknown, as it is usually deflected, reflected, or dispelled.
Sonído: Nnoitra has been shown to use Sonído when discussing Orihime Inoue with Ulquiorra Schiffer. He has also been shown using it in battle, but his skill level with the technique is unknown. He is fast enough to overwhelm a battle-worn Ichigo using his Bankai.
Immense Spiritual Power: Nnoitra has an incredibly high Reiatsu, and is able to fight on par with Kenpachi Zaraki, a captain well-known for immensly high reiatsu. It is because of this high spiritual power that Nnoitra has strong Hierro even greater than Ulquiorra's. He is also just below the power level of the top four Espada, who are strong enough to destroy Las Noches simply by releasing their power. His Reiatsu is golden-yellow in color.
Santa Teresa (Praying Mantis): Nnoitra's Zanpakutō is uniquely different from the Zanpakutō of many of the other Espada since, unlike the basic sword shape of most Arrancar, Santa Teresa takes the form of a giant axe-like weapon bearing two crescent moon-shaped blades fused together at the backs, with a large looped chain connected to the shaft at the end of the handle. The chain is connected to Nnoitra's waist, allowing him to perform long-ranged attacks.
- Resurrección: The release command is "Pray". Nnoitra gains an extra set of arms, which take on an insect-like carapace and clawed hands, with each hand holding a large scythe-like weapon as well. The scythes themselves resemble the appendages of a praying mantis, and have a small golden tassel at the end of each staff. He also gains a golden marking extending from his forehead to below his right eye, as well as a pair of horns on his head, his left horn longer than his right, resembling a crescent moon. His hollow mask also changes, becoming torn, with the teeth extending over the hole itself. The weapons are used by him to both defend and then rapidly attack his opponent, as is seen in his fight with Kenpachi.
Resurrección Special Ability: In this state, Nnoitra's physical abilities are enhanced.
- Instantaneous Limb Generation: Nnoitra can grow an extra set of arms for a total of six, he keeps one set hidden, which he can grow out instantly to perform surprise attacks.
- Weapon Generation: Nnoitra can grow his scythe-like weapons out of the folds of his wrists, allowing him to replace lost or damaged weapons easily. He can also retract the weapons back within his folds when he has no further use of them.
- Enhanced Strength: In this state, his strength is enhanced even further, allowing him to overwhelm Kenpachi Zaraki during their battle.
- Enhanced Hierro:
- High-Speed Regeneration: Nnoitra has the rare ability to instantly heal injuries while in his released from. The power also allows him to regenerate severed limbs. However the weakness of High-Speed Regeneration is that it cannot heal injury to in the internal organs or the brain and will cease working once either scenario happens.
- Cero Gigante (Giant Hollow Flash): An advanced Cero ability that allows him to supercharge an enormous yellow Cero from his mouth before firing it at his opponents in a straight line.
- Tesra Lindocruz (Fraccion)
- Nelliel Tu Odelschwanck (Arch-enemy)
- Kenpachi Zaraki (Enemy and Arch-rival)
- Yachiru Kusajishi
- Ichigo Kurosaki
- Orihime Inoue