If you haven't watched the latest season of Demon Slayer: Kimetsu no Yaiba, everything below is a spoiler!
Ever since Demon Slayer began, protagonist Tanjiro Kamado's evident scar has been a subject of debate. Fans keeping up with the series will know that Tanjiro was NOT born with the scar on the forehead. He got the scar as a young boy while pushing his younger brother out of the way of a falling pot of boiling tea. Tanjiro's scar was a light pink mark on his head when the series began.
However, this wasn't weird at all. After all, even Demon slayers can get burn marks, right? The only thing that WAS weird at the time was that even though Tanjiro's scar wasn't a birthmark, it was identical to the scar on his father's forehead. However, the series didn't address Tanjiro's father's scar, so fans eventually moved on.
As time passed and Tanjiro reached the "final selection," his scar became the subject of debate once more, and rightfully so. After suffering a blow to his head directly where his scar is located, Tanjiro's head is bandaged for the next few episodes. However, when he eventually takes the bandages off, the scar seems to have dramatically changed and looks like a spiky dark red line.
However, the change in the scar was completely ignored by people within the series. This led fans to believe that the difference was simply an animation upgrade to make Tanjiro look even more remarkable. But now, in the latest episodes, we've found out that Tanjiro's scar ultimately DOES have some significance to it. But what does it mean? Read on to find out.
What Does Tanjiro's Scar Signify?
Whenever the Demon Slayer fandom has a question, Shinjuro Rengoku is always around with an answer. In the latest episodes of the Entertainment District arc, Tanjiro fights Daki, an Upper-Rank Six of the Twelve Kizuki. During this encounter, he recalls a letter he received from Shinjuro Rengoku, the same person who told him all about Sun-Breathing.
In the letter, Rengoku explains that the scar on Tanjiro's head is the mark of someone who has been chosen to wield the Sun-Breathing technique. We then see a memory from Muzan rising out of Daki's subconscious. In the vision, we see a man wearing Hanafuda Earrings, the symbol of Sun-Breathing. The man also seems to have a scar nearly identical to Tanjiro's.
Shinjuro's claim at first was hard to believe since he also claimed that this mark is something people are born with, and Tanjiro certainly wasn't. However, we must also keep in mind that Tanjiro's father, who taught him all the various forms of Sun-Breathing, WAS born with a scar on his head.
This means that Tanjiro's Sun-Breathing technique is a thing of destiny, rather than a Breathing Style that any Demon Slayer can learn. It's also possible that Sun-Breathing might be the only thing capable of harming Muzan Kibutsuji.