“The Rengoku family is known for suffering from a curse, which in many eyes is seen as terrible and evil.
Years ago, a survivor of Hantengu's attack saw in a Rengoku the likeness of the being who had attacked him long ago.
Despite not sharing the same background as a priest, this survivor cursed the Rengoku family. It didn't work out as the survivor expected, but that was enough.
The Rengoku family had a long history of problems related to their children, specifically those who were said to be multiples.
It was rare for twins or more to be born in the family, and when this rare event occurred, one of the babies would die one or two weeks after birth, usually the younger one in the case of twins, if there were more, like triplets, all the babies would end up dying.
The Rengoku family decided they wanted to have at least one and at most three singleton children in their families, in order to avoid the curse that would befall them.
When they were young, the Rengokus learned that the reason multiples were rare in the family was because they were naturally selfless, so the younger siblings would look to their older siblings for inspiration.
When they were older, at the age to (perhaps) marry and continue with the family, they were told the truth, so that if they were to have multiples, they would already be prepared for what would happen.”
(AU) Lore related hc but my writing skills are rusty lol
I was inspired by a headcanon I saw a few times on Tumblr, saying that Hantengu could be the reason for the existence of the Rengoku, which is why he's mentioned in the text!
My friend helped me with this, so I tried to refine it even further, but overall, the survivor's deep resentment, fear, and anger caused the curse to come true.