After the battle, Tanjiro returns home with his sister and friends. Later it is revealed that he married fellow slayer Kanao Tsuyuri.
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 marries Zenitsu Agatsuma in the Demon Slayer series.
But when he realizes Nezuko is still alive, Tanjiro's love for her outweighs any other thoughts he may have and his single-minded focus becomes to get her to help. Even when confronted by Giyu Tomioka, the Water Hashira of the Demon Slayer Corps, Tanjiro begs him to spare Nezuko.
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.
Zenitsu's debt is estimated to be around 600,000 yen in modern currency. This massive amount of debt likely came from his 7 ex-girlfriends. Despite all of them being beautiful, they treated Zenitsu like a slave, tricked him as well as robbing him of his money.
During Hashira Training, Zenitsu receives word that Kaigaku had become a demon, and that Jigoro committed seppuku as atonement.
In the Modern World, Tanjiro and Kanao had descendants named Sumihiko Kamado and Kanata Kamado.
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. After her battle against Dōma, Kanao lost usage of her right eye due to the strain of this technique.
Tanjuro Kamado a recurring flashback hero from Demon Slayer : Kimetsu No Yaiba. He was the husband of Kie Kamado, and the father of Tanjiro, Nezuko, Takeo, Hanako, Shigeru, and Rokuta.
Doma grew fond of her due to her beauty and singing ability, intending to keep her alive until she died of natural causes.
Shizuka is seen often teasing Sanemi and making him annoyed, nevertheless, the two had still created a strong bond and relationship with each other. Eventually, after knowing each other for a while, Shizuka finally ended up having the courage and confessed, leading to them getting married after awhile.
Giyu also states how he feels about Shinobu, saying he thinks she is both hardworking and serious, along with stating that she talks to him a lot and mentions she looks pale, implying he might be worried about it.
However, in the Demon Slayer manga Muzan reveals his motivation for attacking the Kamado family. It turns out that Muzan attacked the Kamado family and specifically turned Nezuko into a demon in an attempt to create a demon that would be able to withstand being in the sunlight.
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.
The reason why Nezuko Kamado acts like a baby now, unlike most demons in the show. When Nezuko was turned into a demon, she went into a childlike state. Other demons just became a darker, twisted version of their past self, minus a few memories.
Unfortunately, Gyutaro spots Inosuke and stabs him right through where his heart should be with a sickle imbued with deadly poison.
Zenitsu is a young man with fair skin and downward-sloped, scared-looking eyes that fade from soft brown to gold. He has short, yellow hair of varying lengths, cutting off squarely at the ends where it fades to a darker orange color, that falls in front of his face in uneven bangs.
During Tanjiro and the rest of the Hashiras' showdown with the Demon King Muzan, Tanjiro is mortally wounded and dies. At the same time, Muzan receives a particularly fatal lil' booboo himself. As Muzan is about to shuffle off the mortal coil, he uses the last of his powers to turn Tanjiro into a demon.
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.
Many people brush off Inosuke as yet another tsundere, but that reasoning is only partially correct. As a child, he was abandoned by his mother and coincidentally, was adopted by boars.