Demon Slayer takes place in a world where humans are continually hunted by horrible demons. While they are not invincible, they do have incredible strength that ordinary humans cannot match. The titular Demon Slayers, on the other hand, have perfected their combat skills with the aim of ridding the planet of demons. And to do so, they are on the hunt for Muzan Kibutsuji, the series' main antagonist and King of Demons.

Muzan was Demon Slayer's first demon, giving rise to all subsequent demons. He is the strongest and oldest of them all being the progenitor. He boasts incredible battling powers that would make any human tremble, but even Muzan has a flaw. Despite his enhanced abilities, he has unable to overcome the basic sunshine vulnerability that all demons suffer from. As a result, he has been on the lookout for the Blue Spider Lily, which he feels is the sole solution to his predicament.


What Is the Blue Spider Lily in Demon Slayer?

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The Blue Spider Lily is an important component of Muzan's medication throughout his mortal days. It was the drug that turned him into a demon. Muzan has been on the hunt for medicine since he wasn't the one who produced it and ended up killing his doctor. However, the manga's closing chapters reveal how the blossom has avoided him for ages. Aoba Hashibara, Inosuke's descendant, discovers that the Blue Spider Lily is a unique flower that only blooms two to three days a year – and only during the day.

In the universe of Demon Slayer, the Blue Spider Lily is a mythological flower. It's similar to a regular Spider Lily, however, this one has a blue color instead of the usual red. The Blue Spider Lilies first appear in Season 2 of the anime, however, their significance was hinted at in the Season 1 outro. To properly comprehend its significance, though, a deeper dive into the manga is required.


Why is Muzan so desperate for the Blue Spider Lily?

Demon Slayer's Blue Spider Lily and Why It's So Important to Muzan_1

The narrative of Muzan's transformation into a demon is revealed in Demon Slayer Chapter 127. He was diagnosed with a fatal ailment while he was young, and he died before the age of 20. He murdered his doctor before completing his treatment in a fit of wrath and sorrow. He did, however, discover that the drug did work. It enhanced his body but at a high cost. It made Muzan vulnerable to sunlight and gave him a taste for human flesh, ushering in his journey as a demon.

Muzan's ultimate goal is to obtain an everlasting body that can withstand the sun's harmful effects and allow him to live indefinitely. To accomplish this, he needed to research the medications that were given to him, making him regret killing his doctor. His sole hint is that the cure requires Blue Spider Lilies as a main ingredient, so he devotes all of his time and energy to finding them. Fortunately, because the Blue Spider Lily is so rare and only blooms during the day, Muzan will have a difficult time finding them. After all, sunshine is the demons' greatest vulnerability in Demon Slayer.