Demon Slayer: Was Tanjiro's Father A Demon Slayer? Why Was Muzan Afraid Of Him?

Surprisingly enough, Tanjiro isn't the only remarkable member of the Kamado family.

Tanjiro's father, Kamado Tanjuro, was said to have had the potential to surpass Hashiras like Rengoku and Giyu. Despite his illness, Tanjuro was one of the best Sun Breath users seen throughout the manga, beat only by legends like Yoriichi Tsugikuni (first Sun Breather) and his son, Tanjiro.

He died young due to an unknown disease, but Tanjuro was far more powerful than the average person, even in his feeble state. Some suspect that this was thanks to the birthmark on his forehead (which looked suspiciously a lot like a Demon Slayer's mark) and that he might've been a secret (or former) member of the Corps before an early retirement.

Today, let's take a look at Tanjiro's father and answer these questions about him. Who was he? Where did he learn the Sun Breath? Was he a Demon Slayer?

Was Tanjiro's Father A Demon Slayer?

Tanjiro's Father Tanjuro

Tanjiro's father was not a Demon Slayer. He inherited the Sun Breath (in the form of the Hinokami Kagura dance) as a rite of passage from his elders and passed it down to Tanjiro as tradition required, but he wasn't related to the Demon Slayer Corps.

As far as we can tell, Tanjuro worked as the resident coalman of his village right up until he died. His immediate family had no knowledge or contact with the Demon World (at least, Tanjiro and the rest of the kids didn't), though it is unclear how much Tanjuro knew himself.

It was implied in multiple flashbacks that Tanjuro was aware, to an extent, of the demons. Whether or not he chose to interact with them was the mystery.

Did Tanjiro's Father Have The Demon Slayer Mark?

Tanjiro and Tanjuro's Birth Marks

Tanjiro's father had the Demon Slayer mark. As Shinjuro Rengoku explained, every Sun Breath user naturally has the mark and is able to see and interact with the Transparent World. As descendants of the Kamado family and the last known users of Sun Breath, both Tanjiro and his father got their marks very early on in their life.

Still, the mark didn't guarantee that the individual would become a Demon Slayer, nor was it exclusive to them. Joining the Demon Slayer Corps was a choice every individual would have to make for themselves.

Who Killed Tanjiro's Father?

Kamado Tanjuro

Tanjiro's father died of a mysterious illness a few years before Muzan slaughtered his family. Though the disease was never specified, it left Tanjuro hallowed and weak, and he spent the last few years of his life bedridden. 

However, his dire condition didn't stop him from performing the annual Hinokami Kagura dance. Tanjuro persisted and performed the ritual from dusk till dawn in freezing weather for as long as he could — a nod to his determination and character.

Tanjuro Performing Hinokami Kagura

It is theorized that Tanjuro's disease was related to his Demon Slayer mark since it was stated by Upper Moon 1 that "members of the Corps with the mark never live past 25." But this theory remains largely unproven and has little evidence to form a solid thesis on.

For now, the best bet is that the disease wasn't related to Demon World at all. Tanjuro could've died of cancer or any similar human illness that exists in the Demon Slayer universe.

Why Was Muzan Afraid Of Tanjiro's Father?

Muzan Kibutsuji

Muzan wasn't afraid of Tanjiro's father. Though the striking resemblance to Tanjiro, the man we saw in Muzan's flashbacks wasn't Tanjuro, but Yoriichi Tsugikuni, the first Sun Breather. Muzan knew Yoriichi was one of the few slayers who could kill him and was secretly afraid of him. 

In fact, there's no reason to suggest that Muzan knew about Tanjuro or had any particular interest in him. He might've kept tabs on the Kamado bloodline for centuries, but that was primarily because of Yoriichi and his legacy (which the Kamado kept alive through generations).

Again, the attack on Tanjiro's family was partly due to their relation with Yoriichi and mostly due to their ability to perform the Sun Breath.

Muzan sought to create better, more evolved demons that could stand sunlight. Yoriichi's twin brother, Kokushibo, who rules beside Muzan as the Upper Moon 1, suggested that he try creating those demons using the Kamado bloodline. This was what led to the attack and resulted in Nezuko being turned into a demon, not Tanjuro.

Were Tanjiro And His Father Related To Yoriichi?

Demon Slayer Yoriichi Tsugikuni

If the resemblance between Yoriichi, Tanjuro, and Tanjiro hasn't made it obvious yet: Tanjiro and his father were distant descendants of Yoriichi Tsugikuni. The Kamado family carried on Yoriichi's legacy (of the Sun Breathing Style) through generations and were the last known people capable of using his gifts.

Yoriichi himself was a legendary Demon Slayer and the creator of the Sun Breath, though apart from Tanjiro, we haven't known any Kamado members who joined the Corps.

According to the manga, sometime before his death, Yoriichi once performed the Hinokami Kagura (the dance that's essentially the Sun Breathing Style) in front of Tanjiro's ancestors, who committed the dance to memory and passed it down for generations.

Eventually, Tanjuro would learn the dance as a rite of passage and pass it down to his son, Tanjiro.