He tells him that he will allow
She is awakened by Sanemi, who stabs her in an attempt to provoke her and her brother. Sanemi trying to prove that Nezuko is dangerous, uses his marechi blood as a bait.
Kimetsu No Yaiba. Ep. 23.
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.
In his first appearance, the Wind Hashira Sanemi Shinazugawa discovered Nezuko Kamado and tried to agitate her by stabbing her repeatedly. When that didn't work, he cut his arm in an attempt to get her to bite him and prove she was no different than any other demon, ignoring Tanjiro's pleas for him to stop.
Nezuko's Sunlight Immunity in Demon Slayer is Tied to the Blue Spider Lily. Nezuko having eaten the Blue Spider Lily at some point could explain her immunity to sunlight, and Demon Slayer: Kimetsu no Yaiba has already worked to justify that.
Unlike other demons who survive on blood, Nezuko never really needs it, and she doesn't even consume human food either. Moreover, Nezuko has never shown any signs of undernourishment as she is always ready to assist her brother with her overwhelming strength and deadly Blood Demon Art.
In Demon Slayer episode 23, “Hashira Meeting,” one of the Hashiras, Sanemi Shinazugawa, hated demons so much he wanted to provoke Nezuko into attacking so he could kill her. He even stabbed her multiple time in front of her bound brother Tanjirou.
Giyu is one of the legendary Hashira, and he's brought down demons far more powerful than Nezuko. With his level of skill and impressive agility, he'd easily defeat Tanjiro's little sister. In fact, when Giyu first meets Tanjiro and Nezuko, he almost does kill the latter.
Giyu would still instruct Tanjiro to train to become a Demon Slayer with Urokodaki. As there is no Nezuko, Tanjiro would have no reason to pity demons, and he'll be much more harsh that he would be if Nezuko was alive. Tanjiro would still manage to kill the Hand Demon and come back alive to Urokodaki.
Zenitsu crushing on Nezuko. Upon seeing her for the first time, Zenitsu falls in love with Nezuko at first sight. She apparently views Zenitsu as a "weird dandelion" and did not initially seem to reciprocate his feelings. Although the two are rarely seen interacting together, Zenitsu treats her with affection and care.
So if Nezuko ate a human. and continued to do so over time, her power could rival that of Upper Moon one or 2, and here's why. One, if you're a manga reader, you know, in her base, Nezuko conquers the sun. And 2, her blood demon art can nullify.
Nezuko Has Suppressed Her Consciousness
Frequently, she is pictured carrying or soothing smaller siblings, clearly taking on a maternal role at a young age. However, after being transformed into a demon by Muzan Kibutsuji, the Demon King, she quickly regressed in mental age and maturity.
Her most prominent trait is her extraordinary growth rate, possibly due to the high amount of blood she received from Muzan Kibutsuji when he turned Nezuko into a demon and the fact that she doesn't need to consume human blood to survive.
so nezuko probably ate the blue spider lily and thats why she's immune and the blood mutated. This is correct. From the Wikia: It is also implied that the Blue Spider Lily can nullify a demon's weakness to the sun if it's consumed, which is the reason Muzan was spending centuries searching for the flower.
Thus, Muzan created demons for hundreds of years even when he didn't want to turn someone. Since he didn't know anything about the Blue Spider Lily medicine, he needed others to find the plant for him by happenstance. This is the general reason why Muzan turned Nezuko into a demon.
This willpower is also what helps Nezuko truly utilize her Awakened form, to fight more efficiently. While she might not be as powerful as Muzan himself, her overall strength makes her easily comparable to an Upper rank demon.
Most importantly, Nezuko upholds a vow of silence by remaining mute throughout the series. 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.
However, the trait that sets her apart from all other demons is the fact that she has the ability to conquer the sun, prompting the Demon King to call her the "chosen demon". Abnormal Demon Physiology: As the "chosen demon", Nezuko has several unique demonic traits that set her apart from all other demons.
Nezuko marries Zenitsu Agatsuma in the Demon Slayer series.
Given that she survived the Final Selection, she has excellent combat abilities. But Nezuko single-handedly overwhelmed Daki, showing just how strong she is as a demon. Therefore, it can be assumed that Nezuko would be able to beat Aoi if the two engaged in combat.
Muzan can't control two powerful ladies
One of the demons he can't manipulate is Nezuko (Akari Kitō and Abby Trott), the half-human sister of Tanjiro. According to Comic Book Resources, since Nezuko is able to cling to the humanity she has left, she's also able to block out Muzan's influences.
Nezuko becomes much stronger throughout Demon Slayer. She's stronger or even as strong as an upper moon.
14 She Has A Really Sweet Relationship With The Hashira Mitsuri Kanroji.
Nezuko Kamado
Zenitsu also protects Nezuko multiple times when she is in danger, evident during Zenitsu's first meeting with Inosuke Hashibira and the battle against Enmu in the train. Eventually Zenitsu and Nezuko would marry and start a family as evidenced by their descendants.