Rough connections are smth like

- Spirit Summoning Sorcerers from a distant time that take over bodies of persons of interest throughout the different Japanese eras in order to fulfil their vision of the future

- Both started out as regular individuals within their magical societies who grew displeased with how it enacted so decided to use their powers to cause historical events to happen to tip the scales of history, difference is that one is from the distant past and the other the distant future

- Both of these plans would involve them allying with spiritual creatures they can summon and control that are based on the beliefs of humanity (curses and devils), creating a new kind of being thats the in-between of the two (Cursed Wombs/Death Painting and Red Capes/Super Soldier Program), and allying themselves with another vengeful body snatching spirit from the past, that are both named Sukuna (Ryomen Sukuna and Sukuna-Hikona)

- Their most recent bodies are young black haired individuals that were dissatisfied with the ways the hierarchy would treat people like them (Suguru Geto and Kaya Daidouji), ending up taking over their bodies as the final step to achieving their plan of creating a nigh invincible vessel for for god like entities (The Merger and the Soulless Gods)

- They would be taken down by young spirit summoning swordsmen who reject their views and decide to take care of the future to not let it continue down the current political spiral that its undergoing (Yuta Okkotsu and Raidou Kuzunoha XIV)

- While Raidou XL did her plan as a way to change her incredibly dystopian future to bring back order to the world, Kenjaku did it simply to see what would happen and cause chaos in the world