The now-iconic bamboo muzzle serves as a way of stopping Nezuko from using her teeth, and also keeps her from tasting human blood, which would cause her to lose control of herself.
The muzzle Nezuko wears is mostly there just in a case if she does lose control, she doesn't hurt anyone. If she took off her muzzle, she could possibly hurt someone without the intention or realising when she loses control.
If Nezuko were to taste blood, it's likely that she would lose control completely, forcing Tanjiro and other demon slayers to kill her. So the bamboo gag really protects Nezuko as well as the other humans the slayers may encounter on their journey.
Nezuko would practically be unstoppable in the series for the following reasons: Nezuko has conquered the sun, meaning she can eat humans both daytime and nightime. Meanwhile, other demons can only eat humans at night. After immunity to the sun, Nezuko would regain her intelligence and speech when she was human.
Due to her demon abilities, Nezuko can change her size/age and appear “mature” in a slightly older form or can even make herself look younger and smaller than a 12-year-old.
The muzzle serves as a representation of Buddhist practices. First, it gags Nezuko, preventing her from speaking like a Buddhist monk's vow of silence, but it also is there to suppress her desire to eat humans. Through a Buddhist lens, Nezuko's muzzle is the symbol of a Buddhist monk.
Nezuko and Bipolar Disorder Nezuko's caring personality changed after her family was slaughtered by the home invasion. Nezuko developed Bipolar Disorder due to the mental and physical stress that was put in her body.
Nezuko, the young sister of the main protagonist Tanjiro, has a special Blood Demon Art called Exploding Blood that allows her to ignite her blood into pink flames and even summon it from thin air. Unlike other demons, Nezuko doesn't consume humans to grow stronger but instead rests to unlock her full potential.
Secondly, Muzan would probably… eat Nezuko and Tanjiro in the hopes of obtaining their sun-resistance abilities, and also since he wouldn't be able to convince them to become demons to work under him. This would allow him to become the ultimate demon.
Abnormal Demon Physiology: As the "chosen demon", Nezuko has several unique demonic traits that set her apart from all other demons. Most notably, Nezuko can continuously restore her power without consuming any human blood like any other demon would need to do.
It is theorized that Nezuko was able to conquer the Sun because she comes from a lineage of Sun Breathing users and because she kept a big part of her own humanity i.e. because she never ate human flesh.
In episode 6 of Demon Slayer season 2, Nezuko entered a berserk state to protect her brother Tanjiro, causing her body to develop into that of an adult. She loses her gag, grows a single horn and gains vine-like patterns across her body.
Well, there are many reasons for nezuko's cuteness. She shrinks, she lives in a box like a cat. She plays cute little games when she's bored. She loves giving and receiving pats on the head.
Sanemi stabs Nezuko's box multiple times, prompting her to leave it. Seeing the Hashira's wounded arm, she is transfixed by the sight of his blood.
However, in later volumes, the muzzle is removed and she gains the power of speech in volume 22 then remembers everything and gets her human thoughts again and remembers her name, albeit very broken due to not speaking for more than two years.
3 Rapid Regeneration
With this technique, Nezuko is able to instantly regrow severed limbs and even heal some lethal wounds. She was even able to reattach her own severed head in the blink of an eye which is even more impressive as no other Upper Rank was able to perform such a feat yet in the anime.
The two known demons who broke free of Muzan's curse are Tamayo and Nezuko. Tamayo was able to break free of the condemnation when Yoriichi fought Muzan, nearly killing him in the process. During this weakened state, Yoriichi let Tamayo go, free her from Muzan, and free her from the curse.
With her immense fondness for humanity, Nezuko broke out of Muzan's control, becoming free to do anything at her will. It is unclear if the curse branded to her by Muzan got lifted or not, but she can't speak a word after turning into a demon, and always has a muzzle in her mouth.
Fans later questioned the reason for letting Nezuko live. Fans believed this could have been a strategic move from Muzan. The theory states that Muzan wanted to create a demon that developed an immunity to the sun. Upon doing so, he would consume the aforementioned demon and become invincible.
The particular color of her hair would also be reminiscent of her family's history as Children of Fire, explaining the burnt red tinge at the ends of her hair. This implies that Nezuko's hair color represents the demon blood within her; as the color takes over her hair, she may succumb to her demon side more often.
The tips of her black hair is colored vermilion, and in her hair is a light pink bow tied to make her fringe stay off her face.
As the main threat occupying the position of Upper Moon Six, Gyutaro's Blood Demon Art is tremendously powerful and extremely dangerous. With it, he can perform various attacks using blood from different parts of his body, and project them from his sickles as well.
Demon Slayer: Analyzing the concluding chapters to ascertain Nezuko's love interest. Nezuko marries Zenitsu Agatsuma in the Demon Slayer series.
Demon Slayer fans across the web are protesting the series' portrayal of Nezuko, who transforms from a cute young girl to a large-breasted woman. The Demon Slayer fanbase is in a heated debate over Nezuko's adult form - and whether it's appropriate.
According to the creator of Demon Slayer, Koyoharu Gotouge, Nezuko's biological age is 12. This means that while she has been alive for 14 years, her body has only aged to the point of a 12-year-old.