He's a Lwa from Haitian voodoo. In the context of the family tree here, he was also the first God of Kitzenadro (the realm of fate, basically the bureaucratic place that determines whether a pass-through is going to Heaven or Hell)



He became the god of Kitzenadro when Hades married Persephone, and when Hades gave Persephone Hell as a wedding gift, Kitzenadro became independent as a result, as it wouldn't be fair for either Hades or Persephone if they controlled their half of the afterlife AND fate.



Samedi learned that he was faded to die by one of his sons, and rather than banging it up, he just had any children that were AMAB killed shortly after their birth. One day, in 2017, he was attending a high school football game (he had been a fan of the sport ever since it was invented) and he was at this one in particular because one of his "daughters" was a kicker for one of the teams.



Unfortunately for him, his "daughter" had just come to the realization (but hadn't come out yet) that he was transgender, thus making him a son, and thus when he went to kick the ball during the third quarter, it went astray, and accidentally hit Samedi in the head, causing him to fall from the bleachers and break his neck and die. Thus fulfilling the prophecy.