[SPOILER] might've been the one to kill Shinobu's sister Kanae in Demon Slayer

The demon behind the death of Shinobu Kocho's sister is one of the biggest questions that Demon Slayer fans have after the most recent episode of the anime.

Warning: Demon Slayer spoilers are up ahead!

During the last episode, the current Insect Hashira told her pupil, Kanao, that she would tell her all about the demon who killed her sister so that Kanao (and others) know what to look out for and how to protect the world from letting the demon continue to run rampant. While we don't exactly know the answer to this question, there is only one individual responsible for this crime.

Why Douma may have killed Kanae Kocho

At times, foreshadowing plays a big part in this anime series, as little hints from seasons past often shed light onto why events of the current are playing out the way they do. In the case of Shinobu's late sister, we believe that Douma, one of Muzan's Upper-Rank demons, is the one behind such a tragedy because we were informed before that he absolutely would do it if the circumstances were appealing to him.

When we see a flashback of Douma during the Entertainment District Arc, we see the menacing demon with bodies of slain women wrapped all around him. We believe this was intentional to show that the Upper-Rank demon finds great joy in killing women to the point of flaunting their bodies around him.

This depiction of Douma also feeds into the narrative that Douma and Akaza (another Upper-Rank demon) are complete opposites of one another, as the Akaza, absolutely refuses to hunt women.

After Akaza, only Kokushibo and Muzan are left as possible culprits. However, we fail to see how either one of these powerful demons would go out of their way to kill Shinobu's sister outside of bloodlust or some sort of revenge that we do not yet know about.

Although we don't believe Muzan was behind Kanae's death, we still think he was involved in some way because there's a chance that, like Shinobu, Kanae was also trying to find a way to solve the demon curse. Perhaps Kanae came close enough to a solution, leaving Muzan with no choice but to send Douma out to kill her before it was too late.

Or maybe Douma didn't need a reason.

As it stands, we know very little about Douma to say for sure what his motivations might have been behind killing Kanae. But if our gut is leading us in the right direction, Douma may have done it simply for amusement rather than some ulterior motive to help Muzan or anyone. After all, Douma does come off as a selfish demon, meaning everything he does is to bring himself some joy.

With the next episode of Demon Slayer on the way, we will hopefully soon find out who killed Shinobu's sister and why. Be sure to head to Crunchyroll on Sunday, May 26, at 10:45 a.m. PT (or 1:45 p.m. ET) to stream the new episode!