There was one character that really caught my attention in the third season of Demon Slayer: Kimetsu no Yaiba and they were barely on the screen. Just who is the Number One Upper Demon Moon?
Demon Slayer: Kimetsu no Yaiba: Katanakaji no Sato-hen (Analysis) – The Number One Upper Demon Moon
The real answer right now, as someone that’s only seen the anime and read two volumes of the manga, is I have no idea. I don’t even think they mentioned his name, although all the other Upper Demon Moons seemed to give him a particularly wide berth. Even Muzan didn’t seem to address him. So, who is he? Well, if appearances are to be believed, he looks very much like the demon slayer that almost killed Muzan many years ago. You might remember the vision from the first season of a guy with the Hanafuda earrings. Yeah, the same earrings that Tanjiro wears.
I believe it was Muzan that was experiencing the memory we saw when he was confronted by Tanjiro way back in episode eight. It was enough to make Muzan order his demons to kill Tanjiro there and then. Something about those earrings worried him. Or maybe, it was who they represented. So, it was quite the surprise to see someone who looked just like this as one of the Upper Demon Moons. Does that mean that rather than killing the demon slayer that almost bested him, Muzan turned him into a demon? Makes sense, but that also means that the memory was from more than one hundred years ago because we know the Upper Demon Moons hadn’t changed in that time.
So, when we saw more flashbacks of this guy interacting with someone that looked like Tanjiro but wasn’t Tanjiro it started to come together for me. I don’t think it’s any secret that family is a massive part of this story. Tanjiro’s main goal is to save his sister. We also learnt that the leader of the Demon Slayers Corp is related to Muzan Kibutsuji. This is where my next theory comes to life. I believe that the Demon Slayer that became the Number One Upper Demon Moon made plans for his demise.
I believe he has been working in the background to defeat Muzan, long before he was turned. It would appear that he is somehow related to Tanjiro. Possibly a great-grandfather or even further back. That would make sense as to why Tanjiro’s father knew the Hinokami dance. That would explain why Tanjiro’s scar on his forehead changes in a similar way to those that use the sun breathing technique. Here’s where it gets really interesting. In this season, we saw Muichiro and Matsuri both experience a similar mark. But what could that mean?
Well, I’m glad you asked. If the Number One Upper Demon Moon is a distant descendant of Tanjiro, it’s entirely possible that he is somehow connected to a number of the Demon Slayers. Has he spread his powers through the populace in the hopes that one day there would be enough of them to challenge Muzan? It’s a long-game tactic for sure, but if someone as strong as that realised that they couldn’t defeat Muzan, then it makes sense that they would try to increase their chances, even if they weren’t around to see it.
The big question then is why doesn’t Muzan know of these plans. Maybe, he does. Who knows? Muzan is a bit of an enigma. However, it would explain why Nezuko wasn’t impacted the same way most demons are. Could it be that the Numerb One Upper Demon Moon has some way of shielding parts of his memories or hiding his intentions from Muzan? This season raised a lot of questions and this is by far the most interesting thing to have happened in the series so far.
I think we may yet discover that other Hashiras are also related to the Number One Upper Demon Moon. I’m certain that at least one of them will have a similar mark that will appear on their skin when they use their powers. We’ve already been told that all of the breathing techniques are derivatives of Sun Breathing. The real question is whether that will be enough to defeat Muzan and also if that is the way this series will go. Given the importance of family, I’m not entirely sure that we will see Muzan destroyed.
I think it’s more likely that he will be returned to his human form. Then, he will no doubt go on with his life like he hasn’t been responsible for thousands of deaths because of his demons. It seems a ridiculous idea, but given that it’s anime and the importance it often puts on family and redemptions, I don’t think it’s out of the question. Do I believe that Muzan should die? I’m not sure. Several years back, I would have said yes in a heartbeat, but now, I’m not so sure. If Muzan became human again, no one would benefit from his death. It wouldn’t bring anyone back. However, if he can’t be turned back, then, yes. He’s got to go. I’ve had my ups and downs with this series, but I am invested enough to want to see how it ends. Now, we just have to wait!
Other Posts in the Series
- Season One
- Episode 1 – Cruelty
- Episode 2 – Trainer Sakonji Urokodaki
- Episode 3 – Sabito and Makomo
- Episode 4 – Final Selection
- Episode 5 – My Own Steel
- Episode 6 – Swordsman Accompanying a Demon
- Episode 7 – Muzan Kibutsuji
- Episode 8 – The Smell of Enchanting Blood
- Episode 9 – Temari Demon and Arrow Demon
- Episode 10 – Together Forever
- Episode 11 – Tsuzumi Mansion
- Episode 12 – The Boar Bares Its Fangs, Zenitsu Sleeps
- Episode 13 – Something More Important Than Life
- Episode 14 – The House with the Wisteria Family Crest
- Episode 15 – Mount Natagumo
- Episode 16 – Letting Someone Else Go First
- Episode 17 – You Must Master a Single Thing
- Episode 18 – A Forged Bond
- Episode 19 – Hinokami
- Episode 20 – Pretend Family
- Episode 21 – Against Corps Rules
- Episode 22 – Master of the Mansion
- Episode 23 – Hashira Meeting
- Episode 24 – Rehabilitation Training
- Episode 25 – Tsuguko, Kanao Tsuyuri
- Episode 26 – New Mission
- Season Two – Yuukaku-hen
- Episode 1 – Sound Hashira Tengen Uzui
- Episode 2 – Infiltrating the Entertainment District
- Episode 3 – What Are You?
- Episode 4 – Tonight
- Episode 5 – Things Are Gonna Get Real Flashy!
- Episode 6 – Layered Memories
- Episode 7 – Transformation
- Episode 8 – Gathering
- Episode 9 – Defeating an Upper Rank Demon
- Episode 10 – Never Give Up
- Episode 11 – No Matter How Many Lives
- Season Three – Katanakaji no Sato-hen
- Season One
- Bonus Posts