Oiwa is just one of many deeply determined, revenge-seeking spirits who fill Japanese art and literature. Known as yūrei, these mostly female ghosts won’t let their male wrongdoers rest until they’ve received a proper comeuppance. As scholar Zack Davisson puts it in his 2015 book Yūrei: The Japanese Ghost, yūrei can “never be destroyed, only sated…they want something.”

Death, and the spirits that emerge from it, are essential to Japanese culture. “The spirits of the dead continue to exist in the unseen world which is everywhere about us,” historian Hirata Atsutane writes in his 1812 book The True Pillar of Spirit. “They all become gods of varying character and degrees of influence.” Temples honoring the deceased dot the country, and yūrei continue to be celebrated each August for Obon, the festival of the dead. In Japanese lore, it’s said that ghosts primarily appear in the hottest, most suffocating months—yes, the “dead of summer.”