WARNING! THIS HAS SPOILERS!
Also please respect that this is my opinion!! Please respect!
I have to say as a Yaoi fan I don't like Sebastian x Ciel
I don't like the whole Butler x Master thing. I hate when everyone goes "Oh there are so many hints that they like each other".
Those are what we call in modern time "Fan service"
You guys have remember, Sebastian is a Demon, How they act to anyone is usually either very violent or can be sexual at times (which can also be an Incubus). Sebastian can't harm Ciel because in the contract he has to obey and not harm him until the contract is completed. So how he acts towards ciel is a natural way on how a demon goes really.( Sebastian can be indifferent and deliberately delays Ciel's wellbeing, as he frequently teases him and has put his life in mild danger for his own amusement. Once, he responded to Ciel's kidnapping as "terrible" but only because the tea he prepared would go to waste. He also calls Ciel a "brat" who treats his workers rudely) --- from his Bio
Also not to mention he was mad when Ciel slapped him in the face even though he did what he was suppose to do.
Another prove would be is that if he was to really love Ciel he would have been happy to stay with Ciel forever. Sure he has to starve forever but at least he would have been smiling with Ciel at the end. But No....He was pissed, because not only does he have to starve for all eternality but he can't even say anything else except for "yes my lord"
That's just plain sad.
the age is just wrong Ciel is like 12-13 and Sebastian looks like a guy who is like 22 or 24 (yet he is 1,000 yrs old probably) That is just Wrong. In all honesty the series is way better how it is now then how it would be if it was yaoi, or Shounen-Ai or Shotca. The storyline doesn't really fit into any of the three
Now Ciel x Lizzy is the true pairing in the series. Yes we all know that Lizzy's Voice is freaking annoying at that she broke Ciel Ring. But remember she was very sad to have broken the ring and actually try to buy Ciel a ring that looks almost like his old one so he can forgive her. Lizzy is actually a very sweet girl who only wants to make Ciel smile. She is also his fiancée. The manga shows more Ciel x Lizzy moments then the anime. In the Manga when Ciel was little and playing with Lizzy he did said to her "I am actually glad you are my fiancée" He also blushes and tries his best not to make her cry in the anime and the manga. When she smiles and he notices that she is trying hard to make him happy, he blushes and does really care for her. He almost said that in the manga but Sebastian was with him and he didn't want to show him that he was weak (you know Ciel has to keep his reputation as being a serious person) He does care for her....He even dance with her (without no one telling him too) in the last episode before he left. In the Manga he show's feeling towards her.
The Manga has more story line then the anime and plus it came first before the anime (Duh!!)
So yes Lizzy can be annoying but at least their love for each other is more real. Even though they were told to be married by their parents they do really love each other. Plus Lizzy is badass in the manga. Also if you look at it Sebastian does support the two , he finds it amusing how Ciel acts towards Lizzy
Now IF Kuroshitsuji was a Yaoi anime THEN SebbyCiel would make sense. But it's not so no.
If you still like SebbyxCiel I will respect that but please remember that I am a fan of CielxLizzy and you have to respect that as well.