A rather quiet person who sits in on Princess Hitei's boastful conversations. He shows little emotion and does not get along well with Togame. He has very little qualm with killing people, both inside and outside of Princess Hitei's orders.
He has long red hair that's bound in a ponytail and a tall height and wears a tuxedo-like uniform. His face is covered by a mask that was given to him by Princess Hitei and is written with the kanji for "unconcealed" or "not ninja".
He used to be a ninja under the Aioi Corps, a group that was eliminated by the Maniwa Ninja Corps over 170 years ago during the Sengoku Period. His ninjutsu revolves around the darkness of his surroundings. His ninja style was overpowered by the early Maniwa ninjas and claims Hōō Maniwa is the sole person who knows about the Aioi Corps ways out of the present Maniwa Corps ninjas. He is the only person who has knowledge of Aioi Kempou.
He is seen spying on Togame and Shichika Yasuri after they recovered Kanazuchi.
Observes Shichika's first duel with Nanami and reports Nanami's power and rampages to Hitei Hime.
Leads Togame and Shichika to Biyorigou and reports on their activities to Hitei Hime. Also Kills Maniwa Umigame, who seeks Entou Jyuu, with Aioi Ninpō: Hairōken (Rear Trickery Fist)
Openly Confronts the remaining Maniwani ninjas and kills Maniwa Oshidori in a duel, revealing Entou Jyuu.
He observes Shichika and Togame as they speak to Higaki Rinne and in doing so discovers Togame's identity.
While Hōō and Pengin was on the run, Emonzaemon stopped their movements when they saw him. He figured Hōō would appear here if he waited for them. He states that Hōō has not changed since their last meet. He engaged and Emonzaemon traded blows with Hōō equally. Hōō used Ninpō: Danzaien and he explains to Pengin that this technique was originally by Aioi Corp, called Namagoroshi. He now call it Shinobazuhō Ikasazukorosazu. The fight broked off when Hōō grabbed Mekki and defeated him.
Later, in Owari, under Internal Security, he revealed Togame's identity and marked her as a traitor, Daughter of the former lord of Oushuu, Takahito Hida, and shoots Togame with Jū in the waist without mercy. On the spur of the moment, Shichika could not stop Emonzaemon's projectiles and Togame fell down to the ground. Like always, Emonzaemon asked what would be her last words.
In the end, he kills Togame and later fights Shichika who wishes to be killed by the same man that killed her. He dies at the hands of Shichika and, with his last breath, asks the princess to forgive him for dying for her sake. His mask is currently in the possession of the princess.
Swordsmanship: Emonzaemon carries a pair of swords and uses them with great skill. He prefers to use them instead of his guns, unless they become unusable or the opponent is too powerful.
Ninja Arts: As a ninja under Princess Hitei employment, Emonzaemon is a very skilled ninja. He used to work with the Aioi Corps.
- Aioi Kenpō: Hairōken (Rear Trickery Fist) - This technique lets Emonzaemon instantly slip into the shadows behind his target, letting him confuse or attack them with ease. However, it appears ineffective against foes with a fast reaction speed and/or abilities that can allow them to defend themselves from behind.
- Ninpō: Shinobazuhō Ikasazukorosazu (不忍法不生不殺) - A technique which allows Emonzaemon to slice through flesh with a swing of his arm. This ability was originally known as Namagoroshi and belonged to the Aioi Clan, until they were killed by the Maniwa and the technique was stolen by Hōō Maniwa.
Marksmanship: He wields Jū, a pair of pistols capable of firing projectiles with incredible speed. Since he wields the only pair of guns in existence, this makes him incredible powerful, he can easily catch most opponents off-guard (since most people don't even know what a gun is). He skilled enough to make the bullets ricochet in order to hit his target.
- Ultimate technique: Danzai Entō (断罪炎刀) - Emonzaemon brings out the maximum potential of Entō Jū, creating fire-power that was strong enough to be used in melee against Kyotōryū. It appears this technique is simply Shinobazuhō Ikasazukorosazu supplemented by Entō Jū, but after hearing that Hōō Maniwa now calls Namagoroshi by the name Danzaien, Emonzaemon likely bridged the names Danzaien and Entō to create the name Danzai Entō.
Deviant Blade Poison: As the wielder of a Deviant Blade, Emonzaemon is affected by the "poison" that exists within the sword. This "poison" makes him unwilling to give the sword away.
- His name "左右田" ("Sōda") sounds like "そうだ" ("Sō da"), which means, "That is so" or, "That's right". It was a pun in novel and anime. He was asked: "Your name is Emonzaemon, right?". And he answered: "Sōda Emonzaemon." In this case it can means both his full name or something like, "That's right. Emonzaemon."