History TearJerker / DemonSlayerKimetsuNoYaiba

** As Daki and Gyutaro are dying, they start bickering with each other and blaming each other for how they ended up like this. Tanjiro finds this painful to watch, and tells them that they should at least care for each other, since no one else will forgive what they've done or mourn their deaths.

* Susamaru was hardly a developed or sympathetic character, but as demons go she was one of the less loathsome, seeming more interested in the fun of battle than any sadistic motives. Her CruelAndUnusualDeath by Muzan's curse was absolutely brutal, moreso than many more unlikable demons' deaths, and when she's been reduced to an indistinct pile of meat, she's still alive until the sun comes up, with her mind seeming to have regressed to a state of childhood, asking for her temari ball and begging Tanjiro to play with her. Small wonder Tanjiro calls Muzan a monster, like he truly is as the series goes on.

** It is eventually revealed that Gyutaro was a deformed kid born into poverty who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a prostitute while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get (nearly) burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, so that his sister can recover from the brink of death through demonic blood and so that they can live as powerful demons that take away things from others, instead of having what is theirs taken away by others.

* When Nezuko is finally shaken off by Tanjiro from her demonic bloodlust by singing a lullaby their mother frequently sings to them, Nezuko [[BrokenTears eventually snaps and breaks down crying]]. While much of it does point to a possible realization that [[MyGodWhatHaveIDone she almost gave in to her hunger for human blood]], it is also possible that the memory of her family's past ([[TheLostLenore and their tragic death]]) has just recently come back to her, and only now is she conscious enough to mourn for them. Not helping matters is Nezuko's [[InelegantBlubbering horrifyingly realistic sobbing fit]] (which sounds eerily similar to Bubbles' [[TearJerker/ThePowerpuffGirls heart-shattering crying]] from the episode "[[Recap/ThePowerpuffGirlsS4E2 All Chalked Up]]" in ''WesternAnimation/ThePowerpuffGirls'', no less), which would definitely encourage the viewer to [[TheWoobie give the poor girl a hug]]!

* When Nezuko is finally shaken off by Tanjiro from her demonic bloodlust by singing a lullaby their mother frequently sings to them, Nezuko [[BrokenTears eventually snaps and breaks down crying]]. While much of it does point to a possible realization that [[MyGodWhatHaveIDone she almost gave in to her hunger for human blood]], it is also possible that the memory of her family's past ([[TheLostLenore and their tragic death]]) has just recently come back to her, and only now is she conscious enough to mourn for them. Not helping matters is Nezuko's [[InelegantBlubbering horrifyingly realistic sobbing fit]] (which sounds eerily similar to Bubbles' [[TearJerker/ThePowerpuffGirls heart-shattering crying]] in the episode "All Chalked Up" in ''WesternAnimation/ThePowerpuffGirls'', no less), which would definitely encourage the viewer to [[TheWoobie give the poor girl a hug]]!

* When Nezuko is finally shaken off by Tanjiro from her demonic bloodlust by singing a lullaby their mother frequently sings to them, Nezuko eventually snaps and breaks down crying. While much of it does point to a possible realization that [[MyGodWhatHaveIDone she almost gave in to her hunger for human blood]], it is also possible that the memory of her family's past ([[TheLostLenore and their tragic death]]) has just recently come back to her, and only now is she conscious enough to mourn for them.

* Daki and Gyutaro were truly evil demons who killed countless numbers of people, but their sibling bond is genuine. Gyutaro was a deformed kid born into poverty who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a prostitute while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get (nearly) burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, so that his sister can recover from the brink of death through demonic blood and so that they can live as powerful demons that take away things from others, instead of having what is theirs taken away by others.

** Sanemi, in a vast black space, could see Genya playing happily with their deceased siblings in a bright world of flowers. In the darkness, he hears his mother, sobbing from the fact she killed her own children, unable to join them in heaven. Sanemi understands, wishing to keep her company in hell, so that she won't have to be alone (he knew that she didn't become a demon on her own volition). Then, his father grabs his arm fiercely and pushes him away, telling him it's not his time yet and thanking him Sanemi for being his son. Finally, Sanemi wakes up, completely bandaged and close to death, but alive nonetheless.

* Daki and Gyutaro were truly evil demons who killed countless numbers of people, but their sibling bond is genuine. Gyutaro was a deformed kid born into poverty who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a prostitute while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, so that his sister can recover from the brink of death through demonic blood and so that they can live as powerful demons that take away things from others, instead of having what is theirs taken away by others.

* Daki and Gyutaro were truly evil demons who killed countless numbers of people, but their sibling bond is genuine. Gyutaro was a hideous kid who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a geisha while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, just so he could be with his sister again and to get revenge on the unfair world that made them suffer.

** During the afterlife sequence, while he's preparing to go to Hell, [[IWantMyBelovedToBeHappy he shoos Ume away, telling her to go to the "place with light", since she still has a chance at redemption.]] This only causes her to cry and apologize for being weak. She clings to his back, not wanting to be separated from him, saying that they will always be together, that she will still be his sister even after reincarnation, and reminding her brother about [[AlwaysWithYou their promise]], all while crying violently as Gyutaro finally carries Ume and brings her to Hell with him.
** As Daki and Gyutaro are dying, they start bickering with each other and blaming each other for how they ended up like this. Tanjiro finds this painful to watch, and tells them that they should at least care for each other, since no one else will forgive what they've done or mourn their deaths.

** Tanjiro cries again when he has to leave the dream world because it is not the reality, despite the fact that he wanted to remain there forever.
* During the fight against Enmu, the demon puts Tanjiro to sleep again and shows him how his family berates him on being the only member of the Kamado family to be alive. This obviously [[BewareTheNiceOnes angers Tanjiro.]]

* Daki and Gyutaro were truly evil demons who killed countless numbers of people, but their sibling bond is genuine. Gyutaro was a hideous kid who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a geisha while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, just so he could be with his sister again and to get revenge on the unfair world that made them suffer. In his last moments, he regrets how she ended up, imagining she could have lived a much better life if she weren't related to him, showcasing how despite his jerkass bravado throughout his appearance in the series, it really underscores Gyutaro's nonexistent confidence stems by being treated unfairly and harshly because of his looks. During the afterlife sequence, while he's preparing to go to Hell, [[IWantMyBelovedToBeHappy he shoos Ume away, telling her to go to the "place with light", since she still has a chance at redemption.]] This only causes her to cry and apologize for being weak. She clings to his back, not wanting to be separated from him, saying that they will always be together, that she will still be his sister even after reincarnation, and reminding her brother about [[AlwaysWithYou their promise]], all while crying violently as Gyutaro finally carries Ume and brings her to Hell with him.

* Giyu's past: on the day before his sister Tsutako was to get married, she hid Giyu from a demon and was killed. Later his childhood gets better as he is trained by Urokodaki and meets Sabito who was the same age as him and they become best friends. However, during the Final Selection they participated in, Giyu is injured and stays on the sidelines as Sabito defeats all demons except for the Hand Demon and he is killed. Giyu technically passed the selection but since he did not kill any demons, he has been feeling inadequate ever since and got plagued with SurvivorSGuilt and believed that Sabito should have survived since he was the one who killed the demons.
* For this reason, Giyu does not see himself as the Water Hashira and is distant from the other Hashira, believing himself to be different from them and not worthy of his position.

* Then he tells Tanjiro that he recognizes Nezuko as a Demon Slayer Corps member since she protected the humans on the train. Then he tells Tanjiro, Zenitsu and Inosuke that he believes they will become great Hashira. This makes Kyojuro's death even more heartwrenching as the three boys cry uncontrollably after he passed away.

* Chapter 66: Kyojuro dies following his fight against Akaza. He tells Tanjiro to come next to him for a final chat. He tells him to visit his house as he may find something about the Sun Breathing and to tell his brother to follow his heart and his father to take care of himself. Then he tells Tanjiro that he considers Nezuko as a Demon Slayer Corps member since she protected the humans on the train. Then he tells Tanjiro, Zenitsu and Inosuke that they will become great Hashira and he believes in them. This makes Kyojuro's death even more heartwrenching as the three boys cry uncontrollably after he passed away.

* The reason for Shinjuro's attitude and started drinking alcohol is the death of his wife Ruka. Although he recovers for a while he gets even worse due to Kyojuro's death.
* After Tanjiro leaves the Rengoku house, Senjuro tells his father Shinjuro Kyojuro's message to take care of himself. Shinjuro finally puts the bottle of alcohol down and starts mourning Kyojuro's death.

* As if Kazumi's situation weren't bad enough already, a flashback reveals that he got the bruises on his face when his would-be father-in-law beat him up, blaming him for Satoko's disappearance.

* After Tanjiro leaves the Rengoku house, Senjuro tells his father Shinjuro Kyojuro's message to take care of himself. Shinjuro fonally puts the bottle of alcohol down and starts mourning Kyojuro's death.

* After the fight is over, Inosuke laments that he has not been able to defeat even a single demon, surprising and saddening for a character who loves to fight.

* Zenitsu's life was filled with [[ItsAllMyFault self-doubt and wrong turns]], [[DesperatelyLookingForAPurposeInLife he was always looking for a place to belong]], [[IJustWantToBeLoved to really feel someone loved him]]; it was by accident that Zenitsu got taken into the world of demon slaying by the chance encounter with the elder known as Jigoro Kuwajima, Zenitsu seemly hated training as he felt no progress was made at all, Zenitsu felt like a failure, he wanted to run but Jigoro did his best to steer Zenitsu into the path of the Breath of Thunder, even with all his incessant bawling Zenitsu realized his master Jigoro was the first person to ever truly stick by him, so the news about his seppuku devastated Zenitsu, Jigoro died alone to atone for his other pupil betraying the corps to become a demon, Kaigaku was the cause but even so Zenitsu had some degree of respect for his colleague but Jigoro committing suicide to atone was just too much, Zenitsu's newfound resolve eventually made him triumph over Kaigaku, the once perceived superior disciple, but the real win in Zenitsu's path was his master himself telling him on the way to the afterlife that Zenitsu was his pride and joy, Zenitsu truly found someone who had loved him, the chance meeting that changed his life for the better, even if tears were to be shed along the way.

* Tamayo is revealed by Muzan in their confrontation to have eaten her own family when she turned into a demon, and then ate other humans in despair for a period. Worse, the only reason she became a demon was that she was dying of an incurable illness and wanted to see her children grow up, unlike others who become demon for more power or already crossing to DespairEventHorizon that they think they have nothing to lose. Knowing this makes her tears when Nezuko hugs her far sadder in hindsight; she was likely thinking of her own children. And the grief of losing her husband and her children is likely the reason why she can't reciprocate Yushiro's feelings for her.

* Sanemi's motivation was shortly revealed after. In a flashback, it shows Sanemi having to fight demons on his own with whatever tools he could find before befriending a Demon Slayer and joining the organization. The two bonded together and became best friends. However, after defeating a Lower Rank, Sanemi had lost his friend due to critical injuries. The day after, the Hashira are called for a meeting and Sanemi starts accusing Ubuyashiki of being cowardly and viewing him and the other Demon Slayers as cannon fodder. Ubuyashiki calmly apologizes to Sanemi and explains that he truly wished he could join his fellow Demon Slayers, but due to his weak body, he could not perform the training to do so. He also saw himself as cannon fodder and soon revealed that his son would continue on in his place should he ever fall in battle. And he reveals that he always remembered the names of the fallen Demon Slayers, including Sanemi's best friend and loved them all equally. He gives his best friend's will to Sanemi, which reveals that his best friend saw his own brother in Sanemi and only wanted his brother to live a happy life. This moves Sanemi to tears and thus became his entire motivation to keep his own brother Genya safe and sound.
* The relationship between both Yoriichi and Michikatsu Tsugikuni is really sad when both end up having to duel one another, with Yoriichi as an elder man and Michikatsu now a demon. Yoriichi sheds tears after seeing his older brother in his demon state and Michikatsu felt confusing emotions by just seeing his younger brother as a elder man. Because of the situation that they were in, both brothers had no other decision but to fight each other.
* Chapter 176 shows Kokushibo's last stand against Himejima, Muichiro, and Sanemi. Fearing that he might lose, Kokushibo assumes a monstrous spider-like form. Upon seeing his reflection on Sanemi's blade, he realizes his own hideousness and is filled with shame. A flashback shows a young Yorichii happily complimenting his big brother and asking him if he wanted to become the strongest samurai of the land. The young Yorichii then tells him that he wanted to be like his big brother and become the second strongest samurai alongside with him. The flashback makes Kokushibo question the entirety of his goal throughout the centuries of assuming his demon form. At the end of the battle, he admits to himself that he just wanted to be like Yorichii.

* Chapter 179: Tokito and Genya both die. Tokito reunites with his twin brother in the afterlife and tells him how he was happy with is life and that protecting his friends with his life is not pointless. Meanwhile, Sanemi sees Genya's body and starts screaming as he starts turning to dust. Genya apologizes and thanks Sanemi and calls him nice as Sanemi can only scream and cry to the gods not to take his only remaining family from him. The worst thing has come to pass, all of Sanemi's efforts to prevent Genya from harm and away from demon slaying business has been AllForNothing.

* Chapter 186 reveals why Yoriichi, who hated hurting people despite his talent, become a demon slayer. After running away to avoid being his father's successor for his brother's sake, he met a recently orphaned girl named Uta who eventually became his wife. When she was close to giving birth, Yoriichi left their home to seek a midwife, but got sidetracked by an old man who wanted to see his dying son. By the time he returned, he found Uta dead at the front door, murdered by a demon with their child. Yoriichi spent ''ten days straight cradling Uta's body in shock and despair'' before being found by Rengoku's ancestor, who convinced him to properly bury them. He decided that day to become a demon slayer. The following chapter then reveals that the fallout of his failure to kill Muzan for good in addition of sparing Tamayo, who was under Muzan's clutches and wasn't a bad person at all once she was freed from him, resulted in him being exiled from the Demon Slayer Corps and the weight of his failure haunts him because he knows many more will die to demons because of it. It also underscores how the corps is failing to understand their adage due of their grief and trauma of being tormented by evil demons, from destroying all evil, to simply killing demons regardless whether they did violate ethics or not, somehow that the present narrative tackled with in regards to Nezuko.

** Gyomei refusing medical treatment from the Kakushi and telling them to let him die as his last wish. As he's passing on, he's able to reconcile with the orphan children that he looked after and died from the demon attack. Both sides apologizing for Gyomei failing to protect them and the orphans who ran away from the temple during a demon attack (they were trying to get weapons for Himejima, but got hunted down). Then, Gyomei embraces the orphans tearfully as he joins with them together in the afterlife.

** Yushiro is still alive after all this time and is known as a mysterious, yet famous painter who depicts the same subject in most of his paintings. Said subject is none other than [[TheLostLenore Tamayo]].

** Daki and Gyutaro were truly evil demons who killed countless numbers of people, but their sibling bond is genuine. Gyutaro was a hideous kid who was hated by everyone, even his own mother. It was only after his sister Ume (which would later become Daki) was born that he found happiness. Ume started to work as a geisha while Gyutaro became a debt collector. One day, however, a customer tried to assault her and she countered by stabbing his eyes out. This caused her to get burned to death while he was away. Enraged at this, Gyutaro accepted Doma's offer to become a demon, just so he could be with his sister again and to get revenge on the unfair world that made them suffer. In his last moments, he regrets how she ended up, imagining she could have lived a much better life if she weren't related to him, showcasing how despite his jerkass bravado throughout his appearance in the series, it really underscores Gyutaro's nonexistent confidence stems by being treated unfairly and harshly because of his looks. During the afterlife sequence, while he's preparing to go to Hell, [[IWantMyBelovedToBeHappy he shoos Ume away, telling her to go to the "place with light", since she still has a chance at redemption.]] This only causes her to cry and apologize for being weak. She clings to his back, not wanting to be separated from him, saying that they will always be together, that she will still be his sister even after reincarnation, and reminding her brother about [[AlwaysWithYou their promise]], all while crying violently as Gyutaro finally carries Ume and brings her to Hell with him.
** Akaza had one of the most tragic lives in the manga. And that says '''something''' to a series already rife of [[TragicVillain Tragic Villains]], especially to someone who managed to earn the ire of the main characters as well as the fandom for being the one who killed [[BigBrotherMentor Rengoku]], one of the beloved characters in the series. Born as Hakuji, he lived in poverty with a sickly father. This forced him to pickpocket and commit crimes from a very young age to obtain money for his father's medicine. His filial piety was not rewarded, however, as his father committed suicide so that he would not be a further burden and Hakuji could live an honest life. During his mourning, he got into a fight and was scouted by a martial artist. Things began to start looking up when he was accepted as a disciple, and he even fell in love with the master's daughter. His happiness didn't last long, as some rivals who wanted their dojo poisoned their water supply, killing his new family. Enraged, he charged into the rivals' dojo, brutally slaughtering every one of them. Muzan found him shortly afterward. Amazed at his strength, he forcibly turned the broken Hakuji into a demon, who only said he ''just didn't care anymore''. Losing his human memories, as the demon Akaza, he once again started pursuing strength, which he then realizes was meaningless as he has longer anything to protect. His anger towards the weak? It's actually his righteous fury towards the rival dojo who couldn't face him and his master in a fair fight and thus resorted to horrible and cowardly deed that lead to the deaths of his master and would-be wife, being twisted by his grief and Muzan's influence. However, the spirits of his father, master, and lover manage to reach out to Akaza and convince him to return back to normal. In the end, Akaza turns back into Hakuji and tearfully embraces his lover, repeatedly asking for her forgiveness for not being able to protect his loved ones. She's just glad that he remembers them and tearfully welcomes him back, also embracing him. He hits himself instead of Tanjiro and Giyu, subsequently stops regenerating as he realizes who he wants to kill the most: ''himself''. Even his appearance can elicit this trope after his DarkAndTroubledPast was brought to light that really shows his status as a FailureHero now a TragicVillain: his hair has the same colors of Koyuki's [[PinkMeansFeminine kimono]], his powers showcase a snowflake and fireworks imagery that comes straight from Koyuki's [[SnowMeansLove name]] and their promise to see the fireworks together, and his ring-like tattoos that were branded to him as a human because of his criminal background due to his noble desire to help his ill father now covers him from head to toe, symbolizing that by crossing DespairEventHorizon, he condemns himself to Hell by becoming a demon under the service of the BigBad who callously uses the young man's grief and anger to suit his own purposes.
* Tamayo is revealed by Muzan in their confrontation to have eaten her own family when she turned into a demon, and then ate other humans in despair for a period. Worse, the only reason she became a demon was that she was dying of an incurable illness and wanted to see her children grow up, unlike others who become demon for more power or already crossing to DespairEventHorizon that they think they have nothing to lose. Knowing this makes her tears when Nezuko hugs her far sadder in hindsight; she was likely thinking of her own children. And the grief of losing her husband and her children is likely the reason why she can't reciprocate Yushiro's feelings for her.
* Zenitsu's life was filled with [[ItsAllMyFault self-doubt and wrong turns]], [[DesperatelyLookingForAPurposeInLife he was always looking for a place to belong]], [[IJustWantToBeLoved to really feel someone loved him]]; it was by accident that Zenitsu got taken into the world of demon slaying by the chance encounter with the elder known as Jigoro Kuwajima, Zenitsu seemly hated training as he felt no progress was made at all, Zenitsu felt like a failure, he wanted to run but Jigoro did his best to steer Zenitsu into the path of the Breath of Thunder, even with all his incessant bawling Zenitsu realized his master Jigoro was the first person to ever truly stick by him, so the news about his seppuku devastated Zenitsu, Jigoro died alone to atone for his other pupil betraying the corps to become a demon, Kaigaku was the cause but even so Zenitsu had some degree of respect for his colleague but Jigoro committing suicide to atone was just too much, Zenitsu's newfound resolve eventually made him triumph over Kaigaku, the once perceived superior disciple, but the real win in Zenitsu's path was his master himself telling him on the way to the afterlife that Zenitsu was his pride and joy, Zenitsu truly found someone who had loved him, the chance meeting that changed his life for the better, even if tears were to be shed along the way.
* Kanao's early years were filled with so much abuse that it ended up breaking her free will and started repressing her emotions just to cope up with the abuse. Hell, her parents didn't even give her a name. It also didn't help that her parents sold her into slavery. If it wasn't for Kanae and Shinobu's [[HappilyAdopted intervention]] her story would be quite different. As for her free will, it only took a small encounter with Tanjiro that helped her get rid of relying on single coin flips to decide on her own.

* Dimensional Infinity Fortress Arc: