Hajiro Shaku'un

Hajiro Shaku'un is the main protagonist of Meiji Boy. He is a Demon Neighbor currently affiliated with Border's Tamakoma Branch, and previously affiliated with the Twelve Kizuki, and then Tamayo. He held the position of Upper Rank Three until he was defected by Tamayo a little over 100 years before the start of Demon Slayer. However, due to not eating any humans over that century, Hajiro has grown weaker. Tamayo stated he would only be capable of reaching Upper Rank Six.

He currently uses his human name, Hajime Tsukishima, as his fake name after Takumi Rindo said it was too depressing to use normally and he should use a more fitting name for a newcomer. He is, or was, a marechi.

Background
Hajiro was born Hajime Tsukishima during the late Azuchi-Momoyama Period in Kagoshima Prefecture. His family was nothing particularly special but because Hajime was a marechi, he frequently attracted the attention of Demons. To protect his family and lessen the guilt he felt over bringing them trouble, he taught himself to fight with a blade. Hajime learned very early on that Demons could not be killed without being exposed to sunlight and thusly made what he called the Death Spot, where he would lock Demons up to burn in the morning. Despite protecting his village, he was hated by his family.

His reputation piqued the curiosity of Upper Rank One Kizuki, Kokushibo, and was admittedly impressed by his talent, though unpolished. Bored, he offered to teach Hajime, though he didn't trust Kokushibo and refused. The next day, his parents tried to kill him, and Hajime killed them instead, tired of their treatment of him. This resulted in his hometown ostracizing him, and he was found by Kokushibo once more. Hajime agreed to learn under him and, having realized how angry humans are from how horribly they were to him despite fighting off the creatures his presence brought, consented to being turned into a Demon.

He was named Hajiro Shaku'un and, having lost his memories, became an embodiment of wrath and hatred, earning himself the monicker Oken-o-sama (皇嫌悪様 Ōken'o-sama, lit. Lord Imperial Wrath). At some point, he was promoted to Upper Rank Three of the Twelve Kizuki and created Shameful Breathing.

Hajiro met Tamayo a little over 100 years prior to the start of Demon Slayer, and became curious about how she broke from Muzan, having resented every other demon since he became one himself. She managed to free him, too, from Muzan's control, and he became a guard of some kind. He does not get along very well with Yushiro, but this disagreement is only surface-level, as the two have created a strong bond over the years.

A few decades before Tanjiro is sent to Asakusa, Hajiro was finally found by Muzan and was taken into the Infinity Castle. Muzan tried to kill Hajiro but he leapt through one of the doors halfway through its creation and was somehow thrown into another dimension entirely. He is considered a Neighbor because, in Border's timeline, Demons never existed, and he is seen as someone from a different enough dimension to be labelled as such.

Appearance
Hajime was a relatively lean young man with lightly tanned skin, orange hair and brown eyes. He usually wore a yukata turned black from ashes and incense. He always had a katana he'd pilfered off a Demon a few years prior to his first encounter with Kokushibo. Hajiro is a relatively lean young man with pure white skin, hair, black sclera and gold irises. Upon arrival in Mikado, he was wearing white robes, resembling a bastardization of a kimono and hakama.

After being assimilated into Mikado, Hajiro began to wear a yukata, refusing to wear modern clothing unless absolutely necessary. He does, however, wear the Tamakoma Branch jacket, upon Yuichi Jin's insistence.

Personality
As a human, Hajime was very friendly, warm and open. He was selfless to the point of being blind to others' flaws and highly altruistic. His mind was changed after his parents attempted to murder him.

As a Demon, Hajiro became very cold and distant. He has an inexplicable hatred for parents and those with selfless personalities like he had as a human. He doesn't like hurting children, but will stop at nothing to kill anyone older if they display behavior similar to that he had in life. After Yuichi spent a lot of time trying to earn his trust, Hajiro told him: "People can end up like me. Full of hate and anger. I don't know why I'm angry, but that anger must have been what made me want to be the monster I am now."

The amounts of self-loathing he has are almost invisible beneath his aggression toward everything else. The way he talks is as if he sees himself as the best and superior, when in reality he desperately wants to find something that can kill him. He claims strength is wasted on humans but, as Yuma Kuga notes, Hajiro wants to watch the world around him flourish despite his presence spreading hatred. He always presents himself as a menace and something that must be destroyed, but this is motivated by his desire to see human children protect and keep protecting, unlike him, who feels like his existence is shameful, and a mistake.

Not once, as a Demon, has he ever killed or intentionally harmed anyone roughly twelve years old or younger.

Yuichi Jin
As of the present, Yuichi is one of the two humans Hajiro truly trusts. Yuichi was the first to see past his anger and see how all that anger is really toward himself, to punish himself and make himself more hated, feeling like he deserves it. Yuichi insisted to Hajiro that he can just tell him anything without feeling shame. It takes a long time for Hajiro to even speak to Yuichi first, but at the moment, they are very close friends. Yuichi is the only human Hajiro has ever claimed to respect.

Takumi Rindo
The other human Hajiro trusts. He helped Hajiro get into the Tamakoma Branch despite having no real reason to other than "I want to." Takumi reminds Hajiro somewhat of his old self, resulting in one-sided tension and irritation. Takumi finally managed to squeeze that information out of Hajiro and he stated quite simply that whatever happened before doesn't matter here.

Abilities
Overall Abilities: As former Upper Moon Three, Hajiro is extremely powerful, having killed a handful of Hashira in his time and having apparently killed 100 Demon Slayers during only his first 100 years as a Kizuki. He used to devour any human he killed, not wanting to waste food nor a lost life. As a Breath Style user, he possesses tremendous levels of strength and reflexes that were further enhanced when he became a Demon.

Hajiro possesses immense strength, speed, stamina, reflexes, durability and endurance. Though he is no longer as powerful as the top three Upper Moons, in his prime as a Demon, he was able to combat the likes of Douma in a serious bout. Hajiro has also attained a Demon Slayer Mark, which took form on his tongue.