Tōsen has dark skin and dark-brown braids that move down to his shoulders. He has pupil-less eyes that are a pale lavender and has been blind since birth.
Tōsen wears clothing similar to that of the Arrancar since he left Soul Society with Aizen and Gin; he wears a white sleeveless coat over his standard black shihakusho, black hakama, white boots, black long, fingerless gloves, a band-like visor and an orange rope coming from his right shoulder running across his chest to under his left arm. With this outfit, he carries his Zanpakuto.
Tōsen's creed in life is to "take the path with the least bloodshed"; it was for this reason that he felt it necessary to follow Sōsuke Aizen. Despite this, he knows of Aizen's plan to create the King's Key, which will require the deaths of thousands of innocent people. He was also willing to attack and kill members of his own division while acting as the 5th seat, including Hollowfying his own captain. Tōsen, along with Gin Ichimaru is identified by Kenpachi Zaraki as being afraid of death, this is later confirmed with him saying he only feared being assimilated into the Shinigami culture and dying a pointless death. Also, despite stating many times how much his friend loved the world, he himself never said so, and in fact hated the world that took away his friend.
As former captain of the 9th Division, which is charged with the editing of Seireitei Communication, Tōsen was the chief editor of the journal. He himself wrote a serialization titled "The Path of Justice", which was not very popular, until he began to publish cooking recipes in his articles, which made them more popular among female Shinigami. This also indicates that his specialty is indeed cooking, his favorite dishes being chicken stewed with carrots and other sophisticated ones. He does not like pickled food.
Master Swordsman Specialist: Though he has a personal philosophy that questions the need for violence, Tōsen is highly proficient in the use of his Zanpakuto, which is further impressive with his blind status. During his days as the 5th seated officer of the 9th Division, he was able to fight at a captain's level, going toe-to-toe with Shinji Hirako (although Shinji was focused on halting his Hollowfication process at the time). Tōsen's swordsmanship mastery is even further emphasized by him holding his own against Kenpachi Zaraki, one of Soul Society's foremost experts in swordsmanship, even if it was only for a short time, as well as in a two-on-one battle with 7th Division Captain Sajin Komamura and 9th Division Lieutenant Shūhei Hisagi, holding his own against the two without any trouble.
Shunpo Expert: Tōsen was fast enough to sneak up behind Grimmjow (when he attacked Karakura Town) before he realized it. Tōsen was able to cut off Grimmjow's arm before he felt any pain, and obliterate the arm with a mid-level Kidō before it hit the ground, a testament to his speed. He quickly protected Aizen from Shinji's attack.
Kidō Expert: Tōsen has been shown using high-level Kidō spells without incantation.
Hakuda Combatant: While relying mostly on his sword skills, Tōsen is also competent in hand-to-hand combat, using swift and powerful kicks to easily overpower and throw around other skilled fighters like Sajin Komamura, despite the massive difference in size.
Descorrer (Splitting Void): A technique used by Espada-level Arrancar, and sometimes others, to open a Garganta between the Human World and Hueco Mundo. Tōsen used this to return to Hueco Mundo from Karakura Town.
Great Spiritual Power: As the former captain of the 9th Division of the Gotei 13, Tōsen boasts a great amount of spiritual energy. His skill in the use of his spiritual power is evident, as he uses his spiritual sense to "see". His Reiatsu is pink.
Suzumushi (Cricket): In its sealed state, Suzumushi looks like a regular katana with an orange hilt. The tsuba has a teardrop shape, with the base of the drop arching over the top of the blade, and the point of the drop pointing below the cutting edge. A row of several tiny teardrop-shaped holes decorates the bottom of the curve, and a small ring, approximately 2" in diameter, dangles off the tip of the tear-drop. The ring itself plays a vital role in the activation of Tosen's Bankai.
- Shikai: Unlike most Zanpakutō, Suzumushi has two Shikai commands, each producing a unique automatic effect.
- Shikai Special Ability: Suzumushi maintains its form of a regular katana. Suzumushi's release command is "Cry", which projects a high-pitched tone over a wide area, overloading the hearing of anyone in range and knocking them unconscious. This comparatively humane and painless technique fits with Tosen's self-presentation as a proponent of justice. The ring tone is produced by the vibration of Suzumushi, which Tosen used to free his sword from the chains of Hisagi's Kazeshini.
- Suzumushi Nishiki: Benihikō (Cricket Second Movement: Crimson Flying Locusts): A technique which changes Suzumushi into its Benihiko form. Suzumushi vibrates momentarily and, after Tōsen moves the blade around him in a semi-circle, a trail appears, following the sword's path. The trail turns into hundreds of blades, which rain down on his opponents.
- Bankai: Suzumushi Tsuishiki: Emma Kōrogi (Cricket Final Form: Devil Cricket): Suzumushi maintains its form of a regular katana, though without the small ring. Tōsen holds up his sword in his right hand, and places his left palm against the ring on his cross guard. The ring begins to spin as it releases spiritual energy. As it spins faster, the circle grows bigger and bigger until it's large enough to surround his body. The ring then splits into ten other glowing rings of similar size that encircle Tōsen. With a slash of his sword, the circles go flying outwards and form a circular perimeter over a large area. Once in position, the ten rings begin to generate a black void, which grows in size until it forms a large black dome, which is centered around Tōsen's body and anchored to the ground by the ten rings.
- Bankai Special Ability: The dome creates a vacuum that nullifies the senses of spiritual energy, sight, sound, and scent, what Tōsen calls Mumyō (No Light). The only sense the victim retains is that of touch. Unlike with some Zanpakutō, Suzumushi does not convert itself into the massive dome that it creates during Bankai. Instead, the dome serves as a separate extension of Suzumushi itself, allowing Tōsen to wield its sealed form as a weapon while inside the dome, but preventing him from using its abilities. The technique's main shortcoming is that anyone, not just Tōsen himself, touching Suzumushi's hilt is immune to the dome's effects, so anyone able to grab Suzumushi recovers their senses. The dome only exists as long as Tōsen wills it to, or if he happens to become seriously injured; in either circumstance, the dome shreds apart and dissipates.
- Resurrección: Suzumushi Hyakushiki: Grillar Grillo ("Cricket Hundredth Ceremony: Lunatic Shackles Cricket"): Tōsen begins the release by holding his Zanpakutō upside down. The release envelops him in darkness, transforming him into a bestial Hollow-like creature. In this form, he becomes hunched over, and his entire body is covered with black fur, with a large Hollow hole in his torso. He also possesses four insect-like arms with clawed hands. On the hunch on his back are two long, spiraling horns, each adorned near the points with two rings with chains hanging from them. His head resembles a cricket, with a bilateral line running down the center, large bulbous eyes (which give him sight) and large rings hanging from the side protrusions. At the bottom of the head is a small opening where his mouth is, which has jagged teeth. He has a long, bushy tail, and a double pair of insect wings. While in this form, he also gains the ability to see, which he arrogantly boasted about. In this form, his Reiatsu is black, with a purple outline.
Resurreccion Special Ability: In this form, Tōsen has enhanced versions of his sound-based abilities.
- Immense Strength: Tōsen's Resurrección grants him increased strength, as he grabbed hold of Sajin Komamura's Bankai when it attacked him, and crushed a portion of its blade with one hand.
- High-Speed Regeneration: Tōsen was also shown regenerating his wounds in his Resurrección form.
- Los Nueve Aspectos (Nine Pagoda Finals Kill): Tōsen draws lime-green circles in the air with his claws, creating a massive burst of sound-based concussive force that reverberates out with crushing power. This technique is capable of dealing a fatal blow to Sajin Komamura's Bankai with relative ease.
- La Mirada (The Gaze): Tōsen gains the ability to charge a lime-green Cero in front of both of his eyes. The two Ceros are generated separately, but they fuse together before firing.
Hollow Mask: Tōsen's Hollow mask covers most of his head, neck, and throat, with the exception of a small hole in the back for his hair. It has a smooth white surface, with the only feature being a bilateral line down the middle, separating the mask into two portions. Tōsen's outfit also changes: he loses the orange strap on his shoulder, and gains a chest plate and a pair of small slim shoulder guards with designs similar to his mask. It is able to open up at the mouth area. When it does, vertical lines appear on the top and bottom, giving it the look of teeth.
- Power Augmentation: While wearing the mask, Tōsen's Hollow powers supplement his Shinigami powers, giving him a vast increase in both strength and speed.
- Enhanced Strength: While wearing his Hollow mask, Tōsen gains greater strength. He effortlessly blocks Tenken and kicks Komamura, sending him crashing into the buildings below.
- Enhanced Speed: While wearing his Hollow mask, Tōsen gains enhanced speed, which he uses to overwhelm Hisagi and Komamura.
- High-Speed Regeneration: While wearing his Hollow mask, Tōsen is able to heal his mangled arm, to the point where it does not show any signs that it was injured.
- Sajin Komamura (Best friend)
- Kensei Muguruma (Former Captain)
- Shūhei Hisagi (Former Lieutenant)
- Sajin Komamura
- Kensei Muguruma
- Shūhei Hisagi
- Mashiro Kuna
- Ichigo Kurosaki
- Kenpachi Zaraki
- Yachiru Kusajishi
- Shinji Hirako