In the world of Demon Slayer, Nezuko Kamado stands out as a character who has embodied the struggle between humanity and monstrosity. Transformed into a demon under tragic circumstances, Nezuko's journey is not just about survival but about retaining her human essence amidst overwhelming demonic instincts.
Her transformation towards becoming a demon was because of Muzan. He killed everyone in the Kamado family. Nezuko was the sole survivor and turned into a demon because she was exposed to his demon blood. Although she was unlike other demons. She managed to retain fragments of her human emotions and memories, particularly her deep affection for Tanjiro.
To prevent her from losing the fragment of humanity she had, Sakonji Urokodaki, a former Water Hashira, made her go through suggestive hypnosis. He reinforced the way she looked at everyone by changing her perception to see all humans as family. This psychological technique worked, and she was eventually tamed.
Unlike other demons in Demon Slayer who rely on drinking human blood to regain their powers, Nezuko has a unique way of ensuring she will not give in to her demon nature. She shrank down and slept a lot to regain her powers. This was highly effective because it was non-violent and also assured others that she was not a threat.

With all the efforts put in by her and others in Demon Slayer, Nezuko was successfully different from other bloodthirsty demons. Her interactions with humans are marked by empathy and protection, further highlighting her retained humanity. This is evident in her relationships with other characters, where she is often seen as a wholesome character just hanging out with her brother.
Although her story comes with a unique set of struggles. There are moments that she faced where her demonic nature surfaced, which led to internal conflicts. Yet she strives to suppress her darker urges in favor of her human conscience.
Her interaction with Tanjiro and other characters is proof that reminds the viewers of her humanity and reinforces her resolve to resist her demonic nature. Finally, the way she combined her demon powers with her humanity created a bridge between the human and demon worlds.
Ultimately, her story in Demon Slayer is an allegory for the battle between one's innate darkness and the enduring light of human will. She maintained her identity as a dutiful sister even after becoming a demon. In the end, Nezuko is a symbol of contradiction. The way her character is beautifully written forces the audience to reconsider what is good and evil.
How did Nezuko become immune to sunlight in Demon Slayer
Nezuko’s life changed drastically when she became immune to the sunlight. Because till now, sunlight was a major weakness for all the demons, including Muzan. She overcame her only weakness and further transcended the typical demon limitations. This happened during the Swordsmith Village arc, when her brother Tanjiro had to make a tough decision to leave her under the sunlight to chase a threat.
She successfully survives exposure to sunlight, and this is astonishing to both allies and enemies. Interestingly, to become immune in such a short time became a huge contrast between her and Muzan. He sought power without humanity; Nezuko achieved power because of her humanity.
To sum it up, the character progression of Nezuko in Demon Slayer addresses individuality, strength, and enduring human connection. Having somehow retained her humanity and also managed to develop unique abilities for herself, Nezuko stands in opposition to the traditional demon portrayal in the show. Lastly, the tale serves as a reminder to the audience that willpower, determination, and hope are the real secrets of strength, while kindness will always brighten someone's life.