Hm, not as good as five, had its moments though. Focuses on Akiha er I mean Azaka aka little sister. Except she's Kokutou's real little sister, lol her origin is "taboo" compared to Shiki's "nothingness" and Araya's "stillness," she says it herself she likes kinks. For some reason I have a feeling the actual story in the novel was changed for this movie, but I'm not really sure why. Something felt off about the drug addict thing.