So my theory is that after Ciel and Sebastian defeat Undertaker and rciel, everything will go back to how it was (except for their relationship with Lizzie, there is no fixing that). Ciel and Sebastian are off to another mission, and everything is back to normal, and we will never know who killed his parents. The reason I say this is due to not having any clues or even any possible little hints of who killed his parents. Of course, the Queen must have killed Ciel parents, that's a theory, but what if it wasn't her but someone else, the real master mind who truly wanted the Phantomhive family to end, a character that may or may not already exist. But who knows, we will never find out, the manga would probably end with Ciel going back to his regular life that it with the story. It's a 50/50 that it would end in that way.
Interesting theory. I hope it's not true, bc leaving the biggest mistery and the thing why it even started unsolved is like the worst thing that could be ever done in any story.
So my theory is that after Ciel and Sebastian defeat Undertaker and rciel, everything will go back to how it was (except for their relationship with Lizzie, there is no fixing that). Ciel and Sebastian are off to another mission, and everything is back to normal, and we will never know who killed his parents. The reason I say this is due to not having any clues or even any possible little hints of who killed his parents. Of course, the Queen must have killed Ciel parents, that's a theory, but what if it wasn't her but someone else, the real master mind who truly wanted the Phantomhive family to end, a character that may or may not already exist. But who knows, we will never find out, the manga would probably end with Ciel going back to his regular life that it with the story. It's a 50/50 that it would end in that way.