Isuca

Isuca is both the titular character and the primary force of darkness driving the narrative. Her true nature is that of a Homunculus—an artificially engineered being created by the rival Asahina clan. Rather than seeking a swift end to her nemesis Sakuya Shimazu, she pursues a far more sinister path: systematically targeting those closest to him in order to shatter his spirit completely. Her name is said to be derived from a red crossbill doll, lending an eerie, unexpected charm to this coldly menacing figure.