Demon Slayer is one of the most depressing modern shonen series. Though it's full of lovable characters like the compassionate Tanjiro Kamado and the neurotic lightning-fast slayer, Zenitsu Agatsuma, almost all of them are terribly traumatized and come from heartbreaking backgrounds.

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After all, Demon Slayer's story literally kicks off after the protagonist's entire family is killed and his sister gets turned into a demon. However, though Demon Slayer's vicious demons are irredeemable in most instances, many of them have equally tragic backstories. The audience and heroes alike cried alongside these foes as they spilled their guts about their sad upbringings.

This article contains spoilers from the Demon Slayer manga.

10 Spider Daughter Bore The Brunt Of Rui's Abuse

The Spider Daughter in Demon Slayer.

The Spider Family's very existence is synonymous with tragedy. It spawned from Rui's existential loneliness, so he created a makeshift family of demons. However, his own twisted perception of reality led him to abuse his chosen family members.

The Spider Daughter, for example, bore the brunt of Rui's abuse. Rui constantly berated her and made her feel useless if she couldn't live up to his villainous standards. Tanjiro overheard it and was in complete disbelief that somebody could talk to their own sibling like that.

9 Mother Spider Lived In Fear Of Rui

The Mother Spider Demon from Demon Slayer Getting Killed.

Each member of the Spider Family was a victim in some way. Whether they were victims of Rui or circumstance, none of them lived happily. The Mother Spider dealt with anybody who invaded the mountain with her strings.

However, Rui verbally abused her all the same. She lived in fear of his wrath, and even if she didn't want to hurt some of the people on the mountain, she had no choice. Rui had a reputation for killing those who disobeyed him and replacing them with someone new, so Mother Spider acted solely on her survival instincts.

8 The Hand Demon Was Kept As A Prisoner For The Final Selection

The Hand Demon from Demon Slayer.

At the time, the Hand Demon was the most terrifying demon that Tanjiro faced in Demon Slayer. His huge, grotesque body and grumbly tone was enough to send almost every prospective slayer running for the hills.

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Urokodaki captured the Hand Demon and imprisoned him on Mount Fujikasane with the sole purpose of being one of the Final Selection's obstacles. Not a single slayer-hopeful could defeat him for years until Tanjiro came along. The Hand Demon recognized that he'd become a villain, but nonetheless resented Urokodaki for robbing whatever humanity he had left by taking his freedom away.

7 Yahaba Only Lived To Serve Muzan

Yahaba using his Koketsu Arrow in Demon Slayer.

Yahaba and Susamaru were a pair who Muzan strung along with promises of induction into the Twelve Demon Moons. Unlike his bold and brash partner, Yahaba was cool-headed and played everything by ear. He hated Susamaru's childish personality and preferred a more precise method of wreaking havoc.

Still, Yahaba's story is pretty tragic in retrospect. After all, Muzan literally made him believe he'd be one of the Twelve Demon Moons one day. His life purpose was to gain Muzan's praise. Yet, he died and Muzan moved on from him like he never mattered.

6 Daki Was Burned Alive As A Human

Daki screams in the face of her defeat in Demon Slayer.

Daki and Gyutaro were the Upper Moon Six pair who wreaked havoc and destruction on the Entertainment District. Their fight against Tanjiro and the gang was one of 2022's most epic and fans have been enthralled by the villainous siblings ever since. In a way, they're a very twisted parallel of Tanjiro and Nezuko.

Daki and Gyutaro didn't come from a wealthy family. Gyutaro was hated for his appearance, but Daki was well-loved by the other villagers because of her beautiful looks. Gyutaro ended up using his sister as a shield from other people's cruelty. However, Daki was burned alive as a human after a run-in with a rogue samurai. If it weren't for Doma turning the siblings into demons, Daki would have died within minutes.

5 Susamaru Was Manipulated By Muzan To Believe She Was One Of The Twelve Demon Moons

Susamaru in Demon Slayer.

Yahaba believed that he had to fight harder to make it into Muzan's Twelve Demon Moons. However, it's heavily implied that Muzan tricked Susamaru into believing that she was already one when she wasn't.

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Susamaru's happy-go-lucky cruelty during battle stemmed from how Muzan strung her along. He recognized how badly she wanted to join the Demon Moons, and used her love for playing handball to kill off his enemies. Susamaru may have been one of Demon Slayer's more obnoxious characters, but it's hard not to feel for her.

4 Kyogai Was Used To Receiving Harsh Criticism For His Writing

Kyogai from Demon Slayer.

Kyogai may seem menacing, but his story is one of Demon Slayer's most heartbreaking. Unlike other demons, he preferred not to violently lash out or scream when was upset. He also just wanted to live peacefully without any slayers invading his privacy. Kyogai used to be a writer, but he was so used to his work receiving harsh criticisms.

He was shocked when Tanjiro didn't want to step on his writings or berate them for being terrible, and his kindness brought a tear to his eye. Even worse, Kyogai was so used to receiving verbal abuse that he gave up on writing and wanted to prove himself as a worthy member of Muzan's Twelve Demon Moons, but got ousted. He was still desperate to reclaim his spot. At the end of the day, Kyogai just wants to receive recognition for his work, whether in writing or as a demon.

3 Rui Was A Sickly Child Who Was Turned Into A Demon & Manipulated Into Killing His Entire Family

Rui looks downward in Demon Slayer.

Rui was born with a terrible ailment that made him a very sickly child. He couldn't go outside and play with other children, and his parents always wished him a better life. After negotiating with Muzan, he turned into a demon.

Getting turned into a demon cured his sickness, but he now dealt with a hunger that was only satiated by consuming human meat. He killed his parents, thereby eliminating the only human connection he ever had. Rui started the Spider Family and assumed the role of the youngest child to compensate for his loneliness.

2 Others Treated Gyutaro Poorly Because Of His Appearance

Gyutaro from Demon Slayer

As a human, Gyutaro grew up in poverty. The Entertainment District may seem like it's full of glitz and glamour, but that's only for the top one percent. The people who can't afford such luxuries have to fight for the bare necessities. Gyutaro's mother would beat him constantly since she had a failed miscarriage and couldn't afford to raise a child.

Others constantly harassed and bullied Gyutaro for his appearance and lack of hygiene, which was out of his control. He was left to fend for himself, often resorting to eating vermin off the road for sustenance. Daki's attractiveness made life easier for him, but it was short-lived after she was brutally attacked.

1 Akaza's Human Life Was Full Of Tragedy & Bloodshed

Akaza punching the air with his fists in Demon Slayer.

Akaza is, by far, Demon Slayer's most tragic villain. Anime-only fans only recognize him as the demon who killed off the fan favorite Flame Hashira, Rengoku. However, his backstory drove manga readers to tears. Some might even argue that he's Demon Slayer's best-written character.

As a human, Akaza grew up in a low-income neighborhood and struggled to make ends meet for his sickly father. He resorted to crime to get the money for his medication. This made rounds, and his dad committed suicide so he'd no longer burden Akaza, who was soon banned from the town. A dojo owner named Keizo took him in and promised to teach him martial arts if he'd look after his daughter, Koyuki. Later on, a dojo leader poisoned Koyuki. This sent Akaza into a blind, murderous rampage, killing everybody in the rivaling dojo.

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