Demon Slayer: Here’s When Nezuko Ate the Blue Spider Lily!

Alongside Tanjiro, her younger brother, Nezuko Kamado, is probably the most important character in the Demon Slayer franchise. On the dreaded night that changed the protagonists’ lives, Nezuko was turned into a demon by Muzan Kibutsuji, and Tanjiro made it his goal to find a way to return Nezuko to her human form. At the end of the Swordsmith Village Arc, Nezuko was seemingly turned back into a human, but she actually only developed immunity to sunlight. How? Well, the series never properly explained this, but an extended scene from the anime suggests that Nezuko might have eaten the Blue Spider Lily at one point. In this article, we are going to address that theory.

Did Tanjiro’s mom know where the Blue Spider Lily was?

Fans of Demon Slayer know that the fictive Blue Spider Lily is a major symbol in the series and is very closely related to the main characters, especially Muzan Kibutsuji, the series’ main villain. In this article, we will discuss the flower’s possible connection to Nezuko, but first, allow us to tell you a bit about the flower in the first place.

The Blue Spider Lily is a very potent and extremely rare flower in Demon Slayer. According to reports, it looks like an ordinary spider lily but is blue rather than the typical red tint. The flower is quite challenging to find. Due to its unique character, the flower only blooms for two or three days a year and only during the day.

It only grows in select regions of the world. It then shuts up once more and resembles a huge horsetail weed, but that is when it is useless. Additionally, depending on the geographical and meteorological conditions, it might never blossom at all. This explains why it is so elusive and why its status is so crucial.

Although it enabled Muzan to survive, it also transformed him into a demon. And although it did give him some incredible abilities, it also rendered him sensitive to sunlight, which is why all Demons only work at night.

Muzan has been informed that the Blue Spider Lily may render him invulnerable. Muzan might become invulnerable by ingesting the Blue Spider Lily again, making him immune to sunlight. But this is also where the irony of the situation lies. Namely, Muzan cannot find the Blue Spider Lily since he cannot search for it during the day, although he knows that it only appears under specific circumstances, including daylight. And this is the whole irony of his endeavor, which also explains why it is risky and relatively meaningless from his perspective.

As you can see, the importance of the Blue Spider Lily is truly amazing, but the plant has only been seen in flashbacks, and it has not appeared in the main storyline. We know it exists, but Muzan could not find it. Yoriichi’s wife is supposedly buried in a place where it grows. We know that Kie Kamado, Tanjiro’s mother, knew where the Blue Spider Lily bloomed, and she even showed them to him when he was very little. Although he does not remember the location, he does remember seeing them.

Now that this is cleared, we can explain how this is potentially related to Nezuko.

What happened to Nezuko after she supposedly ate the Blue Spider Lily?

At the end of the Swordsmith Village Arc, Nezuko can conquer the sun, which was a major moment in the series that showed just how special she was, despite being a Demon. While the manga never explained this properly, Tamayo did list some of her thoughts and ideas in a letter written to Tanjiro, suggesting that Nezuko was still tied to her human side more than other demons but also that her blood was special.

In the anime, the contents of this letter were expanded, with Tamayo indicating that there was something “blue” in Nezuko’s blood, which prompted fans to think that Nezuko had consumed the Blue Spider Lily at some point and that this helped her conquer the sun later on. This theory might make some sense, but the rest of the manga doesn’t contribute to its validity.

Namely, the Blue Spider Lily has not been seen or found by anyone in the main timeline, so there is absolutely no way that Nezuko found it and came into contact with it without anyone knowing. Her consuming it as a child makes more sense, but several questions exist.

When did it happen, seeing that Kie Kamado only showed it to Tanjiro and the manga never stated that Nezuko saw the flower? Why would Nezuko consume a medicine with the Blue Flower Lily, as the series does not confirm that she was ill? If she consumed it, why was she not immediately turned into a demon like Muzan?

These questions suggest that the theory is not right, although we’ll have to see whether the anime series expands on it.

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