Moral Event Horizon: The ireedemable sins of some characters cause revenge from the great beyond to happen. The Yotsuya Kaidan story has Iemon who murdered Oiwa's father for getting in his way and tortured a man to death for trying to steal a life-saving medicine. And he also tried to get rid of Oiwa by having his retainer rape her. Also Oume and her family disfigured Oiwa horribly in order to make Iemon dump her.
The Bakenekko story has the whole aristocratic family with the patriarch abusing and raping Tamaki and later beating her to death, because his eldest son also attempted to have his way with her and the rest like Sato helped with the abuse. Only Kayo and Odajima (the family maid and samurai retainer) had nothing to do with all that and fittingly they were the only who made it out alive though badly shaken and horrified by what they heard.