One Demon Slayer character had a similar backstory to Muzan (& it's not Kokushibo)

Demon Slayer has some of the most nuanced and complex characters in anime. In fact, Koyoharu Gotouge’s ability to write characters is unmatched. These characters have played a big role in the series’ success. Therefore, there are plenty of discussions surrounding these characters and the impact they’ve had on the show. Fans seem to be interested in the main antagonist of the series - Kibutsuji Muzan.

He is arguably one of the most hated characters in the series. That being said, fans are quite intrigued by his involvement in the story. They believe that Muzan saw himself in another character that fans know of. The mysterious character in question seems to share something in common with the Demon King himself.

Let’s take a closer look at who the characters are and how they are similar to the main antagonist of the anime series.

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Demon Slayer: How this character has a similar backstory to Kibutsuji Muzan

The person in question is none other than Rui. He was a powerful Lower Moon demon who had spider-like abilities. He was so strong that he nearly managed to kill Tanjiro Kamado and Nezuko. However, the duo was saved by Giyu Tomioka, the Water Hashira in the series. The latter managed to kill Rui with relative ease and did so without wasting any time.

However, there are some similarities between Muzan and Rui in the Demon Slayer series. It might be hard to observe the similarities at first. However, fans will be surprised by the similarities that they share. The first similarity is their origins. Both Rui and Muzan were born with a mysterious illness.

In fact, all of Muzan’s frustration and anger stemmed from his anger towards his own weakness. Rui was born with a very weak and frail body. He was so weak that the very act of walking would put a massive strain on his body.

If we also take a look at Rui’s demonic transformation, the timing of it all could lead us to believe that Muzan saw himself in the young human. Rui was a young child and was offered to fix his body by turning him into a demon. Rui naturally accepted it and then became a demon in the anime and manga series.

What fans might not realize is that Rui was also one of the only demons who had a family of his own. Whether or not Rui’s so-called family could even be called one is a debate for another day. However, it still doesn’t change the fact that Muzan made an exception for Rui.

Muzan wasn’t empathetic in any way, and we have established this in various discussions in the past. Therefore, it’s clear that similarities in their backstories are evident in the preferential treatments.

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Conclusion

The circumstances in which Muzan and Rui grew up were quite similar. They both had weak bodies, and it was the cause of endless frustration. This is also why we believe Rui received preferential treatment from the Demon King himself. Therefore, it’s safe to say that Muzan and Rui’s backstories in Demon Slayer are quite similar.

Stay tuned for more Demon Slayer anime and manga news as 2025 progresses.

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Related links:

• Are Shonen protagonists becoming darker? Explored
• Tanjiro needed to meet this character in Demon Slayer but never did (& it's not Yoriichi)