Alright so yeah, we continue on with this Yoriichi hate train. Kokushibo absolutely despises his twin brother. Personally, my twin brother is great at a lot of things, but I don’t think I could ever hate the kid for it. This guy has some serious black sheep adjacent syndrome going on. From what we have read about him, it’s not like his father didn’t like him. And yeah, so his mom spent a little more time with Yoriichi than him, but with good reason. Unless I’m missing something major, there really is no valid reason why this guy hates his brother so much. Excluding the fact that Yoriichi is super smart and an exceptional swordsman.
Anyways, back to the chapter, shortly after Yoriichi leaves, his father sends someone to bring him back but he isn’t at the temple. He disappears and Kokushibo can live a life without his brother. Kokushibo describes his life, as peaceful for the next 10 years. During that time, he marries and has a few kids of his own. Somewhere down the line, a demon ends up attacking Kokoshibo and his men, and to his rescue low and behold, comes Yoriichi. Kokushibo notices his brother has changed and his swordsmanship is even better than before.
He describes how he felt upon seeing Yoriichi again, which was pure jealousy and hate. Despite feeling all this, he still wanted to attain the same power and strength his younger brother had. In order to do this, he ended up leaving his wife and children, and became a demon slayer.
He eventually got his demon mark, but learned he could not master the breath of sun technique, and developed the breath of moon instead. Kokushibo believed he would catch up to his brother, and soon realized how hard this was. He also noticed that the demon mark that most hunters bore, gave immense power in exchange of shortening one’s own life. Shortly after realizing this, Kokushibo crossed paths with Muzan.
Muzan convinced Kokushibo that if he became a demon, not only would he live longer, he could master breathing techniques. Kokushibo agrees and becomes a demon, eventually crossing paths with his twin brother once again.
He recounts that even after seeing him all those years in old age, he still remembers his brothers face. He couldn’t even remember his own wife’s and children’s faces or his parents. Kokushibu muses on about how he abandoned so much and also mentions killing the swordsmen who knew of the sun breathing forms.
*side note: I just had a thought. I think Muzan slaughtered Tanjiro’s entire family on purpose. Tanjiro himself, uses the dance of the fire god breath technique. Which is most similar to the breath of sun technique. Is it quite possible, Muzan knew of the Kamado family’s connection to Yoriichi and that’s what got them killed.
Yoriichi taught the Kamado from his era,the breath of sun technique, and had him pass the technique down along with the hanafuda earrings. The earrings are specifically worn by breath of sun users. Muzan most likely heard of a breath of sun user living in the mountains, (Tanjuro) and decided to go there to eliminate him.
Only Tanjuro had already passed away already, so instead he kills the man’s family. His bad luck two of the Kamados survived. Let me know what you guys think of this theory.*
Back to the chapter, Kokushibo asks himself why he was unable to leave behind a legacy, and why he couldn’t have become someone important. he then questions his very own existence and the chapter ends.
I think if Kokushibo would have invested more time and energy into himself, rather than his brother, he would have still been great. Instead, he let jealousy and hate drive him to death ultimately. And even though he did become a demon, he still was not able to really surpass his brother or attain the same power as him. Hate to see it. On to the next!