Seijou Kakyoku

Seijou Kakyoku (清浄歌曲, Seijō Kakyoku; lit. pure melody") was a great and powerful Seikōzoku (神聖なレース, Japanese for "Sacred Race") that was punished by the, for  disrupting the balance of souls passing into the  by playing a prank on them. He reversed the Konsō process and sent souls back to the world of the living which made them pray to  attacks. For his crimes,  commissioned a powerful  spell to seal him away and bind his immense powers, it took the combined might of all Thirteen Captains to do this and in the end he was transformed into a small child and then cast into the future by way of  which then was made illegal for normal use. After this event he reappeared as a young plus unaware of his past or his true powers as when he arrived 150 years later he hit his head giving him amnesia.

Unnamed Fourth Arc
During his introduction Seiwa Yumehira and her father Jin Yumehira will find him and take him back to Soul Society of Greece, where they will attempt to break the seal holding him in his child-like state.

Powers and Abilities
High Speed: Similar to, He is able to move at high rates of speed for short burst as he is not used to using his speed. This is usable by circulating the spiritual energy within his legs to unknown and incredibly high levels and then releasing it like a spring in order to propel himself off the ground in a set direction. Soul Manipulation: As a lower key version of his former powers over the soul, Seijou is now able to simply manipulate the thoughts of other souls in order to gain a perk as he uses this often to get his way. This works stronger on weak minded souls and is used by implanting a thought into their head and then forcing it to the surface. To use he makes direct eye contact with his intended target and his eye transforms to show red irises which place his own thoughts into their mind.

Spiritual Power: Currently he is only able to access a fraction of his spiritual power known to him before he was bound in to the body of a child. This spiritual power is about the same currently as a seated officer in the Gotei, which pales in comparison to his god-like aura.

Hand to Hand Combat: Having an adoptive mother who was a member of the Gotei 13, he learned how to defend himself since he had no other real talent for Shinigami arts due to the nature of the Seal. With her training he was able to fight on the level of a seated officer in the catching most off guard due to his age.

Former Powers and abilities
Instantaneous Speed: His speed is truly god-like as he surpasses all known forms of Hoho while moving. He was able to simply envision a destination and it was like the ground moved underneath him, rather than him moving at all.

Kidō Displacement: Due to his nature his body acted as a kidou canceling field able to displace spells as high as 98, even with the incantation, it was for this purpose that a special level 99 spell was made to seal him away.

Reverse Konsō: This ability was known to be the ability to reverse the transmigration process and send souls from the soul society to the world of the living. Being that it messed with the balance of death and rebirth, the soul society punished him for this by sealing him away.

Blank Creation and Control: This ability is what allows Seijou to summon an army of Blanks to do his bidding. Once the Blanks are summoned, he can manipulate their form to perform various feats. A commonly seen form for the mass of Blanks is that of a sword that he can then modify to accommodate the situation at hand. Part of the danger for this ability is that if he were to pull too many at once, the balance of reality would be at risk and if put under enough stress, would eventually snap, causing a rend in space-time to occur and destroy the area in a large explosion that puts even himself at risk.

Memory Modification and Falsification: Part of his control and power over Blanks, living memories, bled into his natural spiritual pressure and gives him a level of control control over the memories of other beings. This includes forgetting how to walk, use their powers, or in dire cases, force their body to forget how to keep the heart beating. He could also falsify memories to alter the opponent's mindset directly.

Zanpakutō Creation and Destruction: Seijou has the power to create Zanpakto spirits from via an unknown method. He can imbue these spirits with whatever power he deems that it should. By the same token, he can destroy Zanpakto by directly interfering with it's soul and killing it.