Why do you love 2CT? Not trying to be rude (I love it too, especially now that it's not really a theory anymore), but I'm curious about the reasons behind your passion for it.
Oh, don’t worry, this is the kind of ask I love to answer!! ;D
(Warning: Long Post)
I personally love 2CT because it completely blew my mind when I first discovered it and understood what it’s about!
I’ve always thought Ciel is an only child (even though it was never confirmed in the manga), so when I first came across a blog post of a Japanese Kuro fan with the title “Ciel Twin Theory” back in March 2014, I thought “What a crack theory, how can he have a twin, he’s an only child?”, but then I read through their analysis and was fascinated about the amount of “hints”, then I bought all the comics and checked every scene that was mentioned in said blog post on my own. And to my surprise, the hints were REAL, they were there all along, some of them were so obvious (like Madam Red’s line “my nephews” or Joker’s line “the Earl and his children”) that I was totally dumbfounded like “How on earth could I have possibly overlooked all these hints until now!!??”.
Then in the same year Yana posted this blog post where she stated that that was exactly her goal: have the readers overlook those mostly subtle but sometimes also obvious hints at first reading and then make them go “WOW!!” when they reread the same scenes - this time with the knowledge of 2CT. Yana’s plan worked out perfectly for me, this theory was so mind blowing and fascinating that I have since become obsessed with it xD
Sadly though, this “2nd reading WOW phenomenon” didn’t really happen in the Western fandom mostly because of language issues. For example, if you reread the Japanese version with the knowledge of 2CT, then you’ll notice that NO ONE actually ever explicitly stated that Ciel is an only child (they usually use vague expressions that can be interpreted as “singular” or “plural”).
However, if you reread the English translation (be it YP or online scanlations) to check the 2CT hints, you’ll find nothing but (inaccurate) translations like “this child” “that child” “my child” “he” “the body of a child” “my nephew” “the Earl’s child” etc which all contributed to the impression that Ciel must be an only child. I’m not trying to blame the translators, they generally do an amazing job, but since most of them didn’t know the 2CT, they automatically made “singular” of all those vague Japanese expressions, and unfortunately this caused the huge confusion and the strong disbelief of 2CT that is so prevalent in the Western fandom x(
Anyway, I do understand that 2CT isn’t everyone’s cup of tea and I’m not trying to tell people to like it, but, like I’ve stated many times, I just want people to acknowledge that 1.) 2CT is a very well thought out plot twist that cleverly takes advantage of linguistical traits (the vagueness) of the Japanese language (that’s why the majority of the Japanese fandom is so fond of this theory and fascinated by Yana’s tricks) and 2.) it’s not Yana’s fault that her linguistical tricks didn’t realy work well in the English translations as they did in the Japanese version :/ (The same thing applies to HP, it’s not Rowling’s fault that the Tom Marvolo Riddle -> I am Lord Voldemord anagram didn’t work at all in the Japanese translation xD)