Descendant of the hunting tribe, Fanalis.Morgiana was a slave. She was emotionless and unfriendly at first, but as time passed after she was liberated, she became more emotional little by little.Although she looks like a normal girl, she can get closer with an enemy far away in an instant. In addition to her strong leg strength which can even enable her to vertically run up walls, she has a keen sense of smell on par with that of a dog’s, can also smell the stench of death emanating from the bottom of the pit and the smell of someone hiding in unseen places. Although weaker than her leg strength, her arm strength is strong enough to send a human flying.

Believed to be the most feared and powerful Toushi around, she even carries the nearly invincible Blue Dragon Crescent Blade from her predecessor as well as the legendary sword Kusanagi; she also has overwhelming chi. She believes her destiny is to die protecting Ryuubi. It is believed by many characters that Ryomou will one day kill her. Presumed to be an old friend of Kakouton and Kakuka. Despite this, however, she seems to have taken an interest in Koukin (this happens only in the "English Adaptation", it is not present in the original JPN manga). She is eventually forced to side with Sousou and plan an attack on Nanyo in order to protect Ryubi from Kyosho's toushi, who would certainly be after her. When she surrenders she is treated as a prisoner. She is handcuffed, beaten, and stripped of her clothing. When Ryubi submits the Gyokuji for Kanu's release, Kanu refuses to accept the offer and stays as a prisoner under her own will. Sousou respects Kanu's wishes and orders the Gyokuji to be returned to Seito. Kanu is able to break free from her handcuffs, clearly holding back while she was captive. She is now treated more fairly while being kept under Sousou's orders.

Notorious for his cruel and deceitful fighting ability, Hisoka has proven to be deadly. His deviousness and volatility has made many opponents have difficulty anticipating his next move, and this has led to him winning many battles. Using Shu powered poker cards as his primary weapon, he throws them with ease and deadly accuracy.

Also, he is very intrigued by Gon and the potential this young boy has to become an adept and powerful adversary. Hisoka, ever looking for a strong opponent, is willing to aid, or at least not defeat prematurely, someone that could develop into a future opponent.

Aizen spent much of his career in the 5th Division, eventually becoming its lieutenant under the former captain, Shinji Hirako. Shinji kept Aizen under his view during this time because he felt there was something dangerous about him. 100 years ago, Aizen's experiments on Soul Reaper/hollow hybrids involved using an unknown method to cause spirits to transform into hollows, eventually culminating in the creation of the Visoreds. He framed Urahara for the hollowfication process and forced him to leave Soul Society.
During that time, Aizen met Gin Ichimaru and Kaname Tōsen, and lured them to his side. Aizen became captain of the 5th Division later on, and Ichimaru became his lieutenant and right hand man. Ichimaru and Tōsen later became captains of the 3rd and 9th Divisions, respectively, but remained loyal only to Aizen.The principal antagonist of the series, he resides in Hueco Mundo together with Ichimaru and Tōsen, commanding an army of Arrancar and Hollows, his ultimate goal being to overthrow Soul Society along with the Soul King and take his place as god of the world.