Demon Slayer: Why does Muzan seek the blue spider lily?

Tulisha srivastava
An image of the mythical blue spider lily from Demon Slayer

In Demon Slayer, the first episode of Season 3 features Muzan’s mentioning the blue spider lily. He expresses his disappointment toward the upper ranks and that they haven’t helped him find the one thing he is looking for.

Demon Slayer’s primary antagonist, Muzan Kibutsuji, is the first-ever demon. He has been around for over a thousand years, hiding in the shadows. Muzan changes several identities and often seems to be researching something.

In truth, he is desperately looking for a rare flower blue spider lily. Even after centuries, Muzan never gave up in his search for it. However, the flower is so rare that he never even got a hint as to where to find it.

This flower is significant to the series as it appears in the outro of Season 1. It was first mentioned in the “Infinity Train Arc” when Akaza reports his inability to find it to Muzan. Here’s why Muzan seeks the blue spider lily.

What is the blue spider lily in Demon Slayer?

The blue spider lily is an essential ingredient in the medicine that turned Muzan into a demon. The flower only blooms during the day for two to three days per year. After that, it closes up and looks like a huge horsetail weed. The Blue Spider Lily doesn’t bloom at all, depending on the climate. 

This flower has medicinal properties, having been used to cure Muzan’s unknown sickness that would have caused him to die before age 20. The medicine was in its experimental stage, making replication extremely difficult. Muzan’s demonization was also caused by the Blue Spider Lily medicine, which gave him a strong physique. 

It also changed his blood to have to transform characteristics, allowing Muzan to generate more of his kind and rule over them. However, the major side effect of the medicine is that when exposed to sunlight, Muzan can disintegrate into ash. He also starts craving human flesh as soon as his e transforms into a demon.

Why does Muzan seek the blue spider lily?

An image of Muzan Kibutsuji in the Infinity Castle from Demon Slayer

Demon Slayer hints that consuming the Blue Spider Lily can negate a demon’s vulnerability to the sun, which is why Muzan spent ages hunting for the bloom. As the strongest being in the world, Muzan’s only weakness is the sun. 

Though the Sun Breathing Technique can harm him, it depends on the user wielding it. The only person who had ever truly harmed him was Yoriichi Tsugikuni. However, the sun is a different case altogether since he can die immediately when exposed to it. 

It hurts his pride to hide in the shadows and never the light of the day. It is also Muzan’s greatest wish to walk under the sun and be free from his torment. However, when he fails to find the blue spider lily, he starts targeting Nezuko, who is able to withstand the sun despite being a demon.  

Demon Slayer can currently be streamed on Crunchyroll. In the meantime, check out our other TV hubs below:

Attack on Titan Season 4 Part 3 | Bleach Thousand Year Blood War Part 2 | Chainsaw Man Season 2 | BRZRKR movie | Jigokuraku Hell’s Paradise | Jujutsu Kaisen Season 2 | Sonic the Hedgehog 3 | Invincible Season 2 

About The Author

Tulisha is an anime writer at Dexerto. In the past, she has worked for Comic Book Resources. She is most knowledgeable about Shonen series, particularly One Piece and Jujutsu Kaisen. You can contact her at