Rengoku’s Dad: Flame Hashira’s Emotional Revelation

Rengoku’s dad Shinjuro is definitely one of the most emotional revelations in Demon Slayer. In this blog, let’s dicuss everything we know about the Flame Hashira’s father and try to understand the actions of Rengoku’s dad’s toward his sons.

Who is Rengoku’s Dad?

Shinjuro Rengoku used to be the Flame Hashira before Kyojuro. He was not just a regular Demon Slayer but a Flame Hashira with many achievements against demons. Shinjuro also passed the fire to become a Demon Slayer to his sons Kyojuro and Senjuro.

The first time we see him is after Kyojuro’s death. Tanjiro, despite his injuries, still goes to Rengoku’s family to impart the Flame Hashira’s last words. When Tanjiro comes, he first sees Senjuro, the young brother of Kyojuro, and then their father appears. 

Rengoku's dad

He holds a jug of wine in his left hand and lashes out at Senjuro and his late son. This upsets Tanjiro. After that, Shinjuro says mean things to Tanjiro because of his earrings and punches his young son while wrestling their guest. After seeing that, Tanjiro gives him a headbutt, making him faint.

Before that, Senjuro says that their dad was a former Flame Hashira.

You can watch this scene in chapter 65 of the manga version or episode 1 of Demon Slayer season 2.

Why Did Rengoku’s Dad Quit Being a Hashira in Demon Slayer?

Shinjuro Rengoku is among the strongest Demon Slayers of the Demon Slayer Corps. Demon Slayer Corps is an organization that rallies many people from all over Japan to work.

They could fight for money, reputation, or the will to purge demons out of the world. Through the memories of other Hashira, we know they come from different cases and reasons before becoming a Demon Slayer.

The Rengoku Clan

However, only the Rengoku family has been focused on killing demons for generations. That clan has a mission of killing demons. Rengoku’s family also provides the Demon Slayers Corps with powerful Demon Slayers, most of which have become the Flame Hashira.

In a flashback of Yoriichi, there appeared a character that looked like Shinjuro and Kyojuro. But, of course, that couldn’t be them because Yoriichi died hundreds of years ago. But we know that the Rengoku family has a considerable tradition of killing demons.

And that tradition has been passed on to Rengoku’s dad, Kyojuro, and his brother. Shinjuro used to be a famous Hashira with many notable feats. For example, he used to save the Serpent Hashira as a kid by killing a Serpent Demon that killed more than 50 people.

rengoku gaiden

In the manga about Kyojuro called Kyojuro Rengoku Gaiden, a demon was looking for Shinjuro for revenge. It was a gun demon. That demon was so full of hate for Shinjuro and now looking for him for revenge. 

Everything Rengoku’s dad has caused him is still in that demon’s mind. He always shakes because of fear and rage when he thinks about Rengoku’s dad. 

Shinjuro has also mastered all the forms of Flame Breathing and other breathing techniques. All the older Hashira, like Sanemi, Tengen, and Himejima, agree that Shinjuro was a solid and experienced Hashira.

But Shinjuro, for some reason, quit the Demon Slayer Corps and became an alcoholic. So, what is the reason for that? There are two main reasons for the change in Shinjuro, making him give up to keep the path of Hashira.

Reason Number 1: The Death of His Wife

The wife of Rengoku’s dad wife is Ruka Rengoku. She was kind, warm, and a driving force to Shinjuro.

Shinjuro was utterly depressed when she died of sickness.

In Chapter 88, we see the letter he wrote to Tanjiro about this. He apologizes to Tanjiro for his behavior the first time they meet and for why he has become so bad. Imagine, one day, the person you love leaves and never gets back to you anymore. What would you do?

Despite his first lousy impression, Rengoku’s dad is affectionate and cares about his family. That’s why he completely changed his personality when his wife passed away.

Reason Number 2: The Origin of Breathing

The second reason is when he discovers the origin of modern Breathing. 

In a book of the Rengoku family titled “Flame Hashira 21,” he discovered that Sun Breathing was the first Breathing created and also the strongest Breathing. He also knows the signals of Sun Breathing users. It’s the earrings and the mark on the forehead.

Other modern-day Breathings are just mimicry and weaker versions of it. After knowing that truth, Shinjuro even read that book up to vent.

rengoku's dad

The Rengoku clan’s famous tradition of killing demons has been due to Flame Breathing. Learning that the Breathing he has been so proud of his entire life is a phony version may have surprised him. The first time he realizes Tanjiro is a Sun Breathing user, he gets surprised and drops the wine jug in his hand. He keeps saying that Tanjiro is mocking him because Tanjiro is a Sun Breathing user.

Shinjuro is probably so proud of Flame Breathing. It is the one that created the reputation of the Rengoku family and helped them kill demons for so many generations. 

Rengoku’s dad’s actions could mean it is still hard for him to accept that Flame Breathing is a weaker version of Sun Breathing.

This touches his self-respect and breaks him. For these two reasons, Rengoku’s dad quickly became depressed and gave up the Hashira position. He falls into alcohol and insults everybody around him, specifically his two sons.

Kyojuro and Senjuro

Kyojuro and Senjuro became the victims of their father. Shinjuro no longer trained them on swords and kept blaming them all the time. He told the two boys they had no talent and that all they were doing was useless and a waste of time.

senjuro crying

With his father’s sudden change, Kyojuro decided to train by himself. He learned Flame Breathing and other Breathing techniques from three of the clan’s books. As a result, he recently became one of the strongest Hashira after a brutal training period.

Senjuro, on the other hand, is too young to do anything. He used to want to give up and not train to become a Demon Slayer anymore when Tanjiro came to his house.


Rengoku’s Dad is Still a Sentimental Father

Why did Rengoku's dad quit being a Hashira?

Even though Rengoku’s dads mistreats his sons, he is still a richly emotional father. 

After Tanjiro returns and Shinjuro receives the last words from Kyojuro for him, the father stops drinking and cries. He cries over the death of his older son.

Next, he starts writing letters to Tanjiro to say sorry for everything he’d done and tell Tanjiro why he had become that way. Later on, in the Entertainment District Arc, Tanjiro remembers his words and gets motivated to fight Daki. (You can find this battle in Season 2 of Demon Slayer)

When the final battle with Muzan happens, Shinjuro voluntarily returns with Tengen and Urudaki to protect the Ubuyashiki family and Nezuko from Muzan.

With that said, the nature of Shinjuro is good. It’s true that he did say bad words to his sons and drank all the time. But deep in his heart, he still is a descendant of the Rengoku family, a Demon Slayer, and a father of two Kyojuro and Senjuro.