I'm still thinking Nezuko will be the one to slay Muzan. Or maybe she figures out something and feeds him her blood, then turns it to fire and literally roasts him inside out. That's what I hope for.
I don't understand why people consider Muzan a "bitch". He's not a warrior. Why would he needlessly risk his life for his pride? That's not being a bitch, that's being rational. He isn't even a man! He's a monster, one whose purpose like all creatures is to live, in his case forever. Interestingly, let's not forget that, (though he doesn't claim to care about them) if he dies so do his entire race. He is like the brain or heart. It must be guarded. He seemed to get REALLY ticked off at Ubuyashiki when he mentioned that to him.
It's really not right to call Muzan a coward either, not in the same way as UM4. He's just selfish to an extent, combined with that reasoning about upholding his race. Let's see how many national leaders wouldn't run if attacked by assassins or military forces if they thought they could survive. All of them, in this day in age. That's just practicality. And let's face it. Even Kokushibou, despite his prowess and pride, shook with fear before his aged and weakened brother. Yoriichi was like the incarante sun god. There is no competing with that.
This is why I hate profanities. "Bitch" in the context applied to Muzan is innacurate and accomplishes nothing but vulgar brovado, from the sound of it. They are utterly meaningless outside of context most of the time, demean the speaker and the readers, and do little to clarify anything for proper argument. I dearly lament the era long ago when such language was banned. It is deeply offensive to me, on every level. Now such words are all that are remembered by the average English speaker in the west.
How glad I am that I've migrated to the Northern Water Tribe! We know respect up here.