Tanjiro Kamado Nezuko is very protective of her brother, and being the sole surviving members of a poor family, the siblings have a very close bond, trusting and loving of one another. He is likely the only one capable of actively calming Nezuko down by calling her name or singing to her their mother's lullaby.
Tanjiro and Nezuko share a strong bond and love each other, but all of that is platonic because they're siblings at the end of the day.
But Demon Slayer introduced Tanjiro's main love interest briefly, and she doesn't really return until the end of the season, when she is fighting against him. His love interest that develops as the story goes on is Kanao Tsuyuri and their romance is quite adorable.
Kanao and Tanjiro would eventually marry and start a family, having two great-great-grandchildren by the names of Kanata Kamado and Sumihiko Kamado between them.
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.
It is confirmed in the Volume 23 extras that Inosuke and Aoi did eventually end up together and that they have two great-grandsons, one of which is Aoba.
Usage of the technique however is highly dangerous, as the tremendous strain caused to the eyes ruptured blood vessels and could cause partial or complete blindness. Kanao used the Final Form to defeat Doma, although it rendered her almost blind in her right eye.
Zenitsu Agatsuma
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.
Shinobu to Giyuu on Kimetsu no Yaiba Official Light Novel. GiyuShino is the het ship between Shinobu Kocho and Giyuu Tomioka from the Demon Slayer fandom.
After the battle, Tanjiro returns home with his sister and friends. Later it is revealed that he married fellow slayer Kanao Tsuyuri. In the Modern World, Tanjiro and Kanao had descendants named Sumihiko Kamado and Kanata Kamado.
However, Giyu Tomioka does not marry anyone in Demon Slayer manga. While romantic subplots do exist in the series, Giyu's character arc focuses primarily on his growth as a warrior and his relationships with fellow demon slayers.
Nezuko's Blood Demon Art is “Pyrokinesis,” which allows her to generate and manipulate special demonic flames created from her blood. It may be because of her unique nature, but her flames have a special ability, making them only harmful to demons and anything related to demons.
Muzan's obsession with Nezuko intensifies as he aims to harness her power and incorporate it into his own abilities, making him impervious to sunlight. With Nezuko now firmly in Muzan's crosshairs, the Kamado siblings and the Demon Slayer Corps face a heightened threat.
Therefore, it is safe to assume that Zenitsu and Nezuko end up together and have kids in the future. This is proof that Zenitsu loved Nezuko and she too came to love him at some point in time.
Kanao never spoke before being adopted into the Demon Slayer Corps and continued to have difficulty speaking after officially joining the other demon slayers. To help with her indecisiveness and other struggles, Kanao often flips a coin she received as a gift. She even uses it to decide when to speak.
Does Tanjiro lose his eye? Yes, Tanjiro loses his right eye. After being exposed to Muzan's poison, his eye is healed but he can't see out of it. Even after returning to his human form, the iris of his right eye remains a dull pink-gray color and the pupil black.
Despite the intensity of his battle against the demon, he never manifested his Demon Slayer Mark, and undoubtedly did not even know the conditions for doing so.
Furthermore, to Tanjiro, Inosuke and Zenitsu's surprise, the Sound Hashira has three incredibly beautiful wives. At the end of Season 2, Episode 12, there's a short scene that explains why Tengen has three wives, named Makio, Suma and Hinatsuru.
In Chapter 205, we see Obanai and Mitsuri reincarnated and married, as they promised before they died, and they are running a restaurant together. In the volume extras it is revealed that they have five kids.
In her final moments, she apologized to Inosuke for failing to protect him and tosses him into the river as an attempt to save his life. She was ultimately killed and eaten by Doma, who claimed to have devoured her to the bone.
It's implied that the characters from the original series have all since died and have been reincarnated in modern day Tokyo in the final chapter of the series, but two key characters confirm that Nezuko Kamado and Zenitsu Agatsuma eventually did have a family together as their great grandchildren, Yoshiteru and Toko ...
Nezuko shrinks to fit inside that wooden backpack or to evade demon slayer swords, and nothing else. So, Nezuko's size can change either way to reflect her emotional state and instinctual needs,. Her size-changing isn't merely a visual gag or a fun party trick.
Tanjiro wasn't born with this scar on his forehead. Rather, he acquired it when tackling his younger brother out of the way of a falling pot of boiling tea. At the beginning of Demon Slayer, the scar was a light-pink, circular mark.