Well Kyonshin is more like a zombie-vampire (according to wikipedia), so they're not a corpse. For example, this "doll" was obviously awake and has shown signs of intelligence and understanding of things, if this were actually a corpse that can't react, therefore, can't give consent, then it would have been unnaceptable. The thing that is weird, for me, is the fact that this Kyonshin is a child, that is a no no.

i should feel guilty about liking this story because it's about necrophilia but at the same time it's so cute so ahhhh idk