Eikichirō Saidō

is an anime-only Shinigami.

Personality
Saidō seems to be a bit lecherous due to commenting on how he had a clear view of a soul's panties in the Fake Karakura Arc as well as making up reasons for why Rukia decided to stay in the real world the main reason being how she was looking for "pleasures of the flesh", however he also seems to be quite level headed and kind as seen in his first appearance in the anime he was playing with some children in Rukongai.

Agent of the Shingami arc
He was sent to find Rukia Kuchiki in Karakura Town. Two years Rukia's senior, he seems to be a low or mid-level Shinigami (supported by the fact he is never seen activating his Zanpakutō), and Rukia states that she has never seen him before, however he did seem to be somewhat important as seen when he first appeared in the series the Onmitsukidō member who had assigned him to bringing back Rukia had stated that he would not have tasked him with that mission had it not been serious. Not long after his arrival he found himself pressed into service assisting Rukia and Ichigo Kurosaki against the Hollow, Grand Fisher. After being wounded by Grand Fisher, he fell asleep. However, he witnesses the conclusion of the battle and sees Ichigo defeat Grand Fisher. After Ichigo loses consciousness, Saidō comments on Ichigo's potential and decides to leave Rukia alone.

Fake Karakura arc
He was seen much later in the series during the Fake Karakura Arc after a group of hollows chasing the soul of a young girl are destroyed due to the sheer reiatsu of the shinigami and Espada noting on the beginning of the battle but also wondering who will win.

Powers & Abilities
Saidō's rank as a shinigami is unknown, as are the extent of his powers. He fought against Ichigo Kurosaki when he first became a substitute shinigami and was easily able to keep the fight in his favor with zanjutsu alone. The full extent of his shinigami powers are still unknown,


 * Expert Swordsmanship Specialist: This was shown when he easily fought against Ichigo (before his training with Kisuke Urahara) due to his long years worth of experience as well as noting how Ichigo at the time relied solely on brute strength.


 * Flash steps practitioner: Due to his affiliation with the Onmitsukidō it can be assumed that he is also proficient in Flash steps.

Zanpakutō
Saidō's zanpakutō appeared to be a wakizashi with a black hilt and gray guard. Due to his brief appearances it is unknown if he is capable of using shikai or communicate with his zanpakutō.


 * Shikai: Unknown/Not yet revealed.


 * Bankai: Not yet achieved.

Trivia

 * After deciding to leave Rukia in the real world it is unknown what had happened to him however it was revealed in the Fake Karakura arc that he was put in charge of a town east of Karakura, although he was referred to as a cheapskate by a young soul due to this.
 * He also seemed to be one of the few shinigami early in the series who did not see Rukia as a criminal.