Demon Slayer:- Tanjiro's mark, explained!

Yoriichi Tsugikuni


In Demon Slayer season 1 we saw Tanjiro's wound on his forehead. He got that while protecting Takeo when he was almost burned by boiling water. A basic looking wound which should not be a concern. However, after final selection, and him healing completely, we see the wound take a different shape. I have a theory about why this happened and it's connection to sun breathing. So let's get started.


We all know that sun breathing is the strongest breathing style in Demon Slayer, after all Yoriichi defeated Muzan with it. Also , a Sun breather is choosen and has an equivalent Demon Slayer mark from his birth. Tanjiro's father Tanjuro had a mark like Yoriichi but Tanjiro didn't, then how come he can use Sun breathing if he was not choosen from birth?

Well, during final selection, Tanjiro got his forehead badly wounded, and thus when it healed the earlier burn marks got healed as well. Fine, but the new mark? What about it? 

Let me explain, remember after killing the demons during final selection Tanjiro showed kindness to them by praying for them never to become demons again. Maybe this is what sun breathing wants. It only chooses the kindest of humans and deems them worthy of using sun breathing. I may be wrong but still there is some logic to it, no one can deny that Tanjiro's training was as tough as hell. But he didn't develop the mark there. So strength is not something this particular style is craving for, although it needs it which I have explained further.

Ok,fine, but after final selection concluded, Haganezka , came with Tanjiro's sword. And yes he was expecting a bright red colour of the sword because he knew that such marks on the face meant that the slayer is worthy of sun breathing. But he was disappointed by seeing it turn black. So, the question is , if Tanjiro was worthy then why it didn't turn bright red? 

Well the answer is simple, Tanjiro had learned water breathing. He was trained in that concept, but he was worthy of sun breathing as well, so maybe the sword was not able to pinpoint an exact breathing style in Tanjiro, because of which it turned black. This was also elaborated by Sakonji Urokodaki that ,slayers who don't know which style suits them best get such black colour on their swords. 

We have even seen this in the second season as well where Tanjiro used water breathing defensively and sun breathing offensively. So it is easy to conclude that Tanjiro boasted both the styles because of which the sword became black. But what about the changed mark he got in season 2 while decapitating Gyutaro? And it even went back to normal. What does that mean?

I think it is due to the fact that Tanjiro's body is not ready, yet, to get the full strength of sun breathing. As we know Yoriichi had many abilities from his childhood. And his strength allowed him to fight his brother even when he was old. Which signifies that sun breathing is not just another breathing style, infact it maybe an untapped reservoir of energy that flows through a demon slayer, significantly increasing the stats of a user. Remember, how Tanjiro fought Daki in season 2. Even when he was fatally wounded, without even taking a single breath , he charged towards Daki. He even nullified Daki's signature move. But after using sun breathing, Tanjiro was so low on stamina that he was not able to stand on his own and was carried by Nezuko in the final episode. Therefore we can conclude that Tanjiro's body is not yet ready to use sun breathing continuously. But if he can use Sun breathing like Yoriichi, then we will be looking forward to amazing action sequences in the series.


So what we take from this breakdown is:-

1. Tanjiro's sword is black because he himself is confused of his breathing style.

2. Tanjiro was not choosen from birth like Yoriichi but, completely unknowingly, he made himself worthy.

3. Sun breathing users need to be superhumanly strong to use the style continuously.

4. Sun breathing maybe an external source of energy and it may provide insane amount of strength and stamina to it's user.

Anyways guys, let me know your thoughts in the comments down below, follow me if you like to read my articles and share them with your anime loving friends. Thanks for reading ☺️☺️.

Comments