[Draugur]

Spoiler for Matsuribayashi-hen / Rika's mother:

Takano wanted to get rid of her, but she thought - given the opportunity - she also could examine her, because Rika's mother used to be the "queen carrier" before Rika was born and therefore is a very interesting object of research. Maybe Takano also wanted to punish her cruelly for trying to get in her way. I think she says to Okonogi that "it would be boring just to kill her, let's dissect her alive" or something like this. The bit about not using anesthesia is only in the manga version, as far as I know.