Houssem
AUTHOR! I suggest the BAKI universe for the next world, it is reasonably stronger than Demon slayer, and the progress of the martial arts of the Mc will be gigantic not even speaking about all the truly EPIC fight scenes you can make taking dozens of chapters to FINALLY reach the strongest creature, at which point the Mc can win on lose. And to recite a bigger challenge and as a result better results the Mc can even teach a breathing method to the characters.
Yes Yujiro can't kill muzan because of his healing factor which will only make the oni king a long lasting punching bag.
Amon91:So.. Yujiro can kill Muzan that is what you are saying..(im no fanboy i just say facts)