Wait...what!?

So 500 years ago, Ichinose family was powerful
A beautiful girl was born there
The 2 eldest brothers fought over her 
2nd brother won
1st brother was a sore loser
Impregnated the girl, castrated his brother
Threw them outta the family
They created their own religion 
But the Hiragi did not overthrow them
Bcz they were generous and FORGAVE THIER SINS?!
I'm sorry who is the SINNER here, again?
Common sense stats drop to ZERO
P.S.: Thanks for the translation though...It is appreciated 

