Nnoitra seems rude and lecherous, accented by his snake-like eye and his nickname for Orihime Inoue, "pet-sama". He even asks Ulquiorra how far has he gone with Orihime's "training", and Ulquiorra turns away and calls him disgusting. In flashbacks to his time as the 8th Espada, he is shown to be a firm believer of male chauvinism as he constantly tried to see that women who are deemed stronger than men, such as Nel Tu, set to more "appropriate" inferior ranks. Though he initially appears to be very sadistic, he has no desire to kill those he sees as weaklings because it does not help prove that he is the strongest Espada which he is quite concerned in proving. However, he has no problem fighting strong fighters who are injured and exhausted, a trait Ichigo and Grimmjow both berate him for.
Despite the fact that he resents females, he is not totally emotionless when it comes to his subordinates. When his subordinate Tesla engages Kenpachi Zaraki he screams for Tesla to get back before Tesla is killed. However, the prospect of a new battle quickly erases this feeling from his mind.
His zanpakutō, Santa Teresa, Spanish alternative name for Praying Mantis, Japanese for "sacred crying mantis"), takes the form of a giant ax-like weapon bearing two crescent moon blades fused together at their backs. It is shown via several flashbacks that it used to only have one crescent. When released, Nnoitra gains two additional pairs of arms, and each of his hands gains an identical scythe-like weapon. Nnoitra's wounds heal almost instantly in his released state, and he can also regenerate severed limbs.
Nnoitra is drawn to the site of the battle between Ichigo Kurosaki and Grimmjow Jeagerjaques. While he tortures the exhausted Ichigo, his former companion Neliel Tu Oderschvank returns to what is revealed to be her adult form and attacks Nnoitra to protect Ichigo. Though she almost defeats him yet again, her amnesia returns and she is left at his mercy. Kenpachi Zaraki soon arrives to help them, and he and Nnoitra exchange increasingly more devastating blows, each finding great enjoyment in the fact that they can survive one another's attacks and therefore prolong the battle. After a long and destructive battle Nnoitra dies what he believes to be a "warrior's death"; his life ends a split second before his body hits the ground.
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