Sorry for late my answer.
Yes I know that the name of "BlackMoonWhiteSun" can be a name for a IchiRuki group, but well, people take that name because exist a theory that Ichigo is the Black Moon (for obviously implications) and Orihime is the White Sun (that's because Aizen say twice times that Orihime is the Sun in Hueco Mundo arc). I'm not imppliying in the name, I didn't made the group, and I didn't decide or vote that name, personally I don't like it because it have IchiRuki connotations...but, well, that's the name of the group and I join them because is a group of my OTP.
Well that's the shipping war XD. I know that some people (IchiHimes and IchiRukis) can be crazy and really annoying.
This is the most difficult question...because some people don't know what they like something. I mean, What do you like...a flavour of an ice cream and not another? Or what some people prefer the summer and they don't like winter or anything? Is the same with the pairing, the people won't have real reasons to like a pair, and they don't need to have a reason. Why they need to explain the reasons to like a pair?
Oh, no, no, no! I have to be more specific XD. Actually I had a good childhood and have a good family XD. No it's only that I have been bullied for my nationality (I'm foreigner) and well, the histoyry between Orihime and Tatsuki is identical like me and my best friend (she even had the same looks that Tatsuki, and she win a second prize in a national competition).
Well, first Orihime was be related with flowers,white, princess...so she don't have just one meaning.And secondly, she specified that she want to be the rain to conectted with other people as the sky do with the earth (I think that it's a way to say that she want to make a bond with Ichigo). I don't think that is so horrible to live with Orihime that any person can be depressed (and I don't think that is the intention of the author to say that...I mean, many people decide to move on with her for a reason).
But I have another question, if you don't have a problem. If Ichigo and Rukia became a pair, What will happen with them? Rukia have to left her work to live in the Human world or Ichigo have to left his family to go to the SS (both have specified that they love their homes and they don't want to leave those places)? Also, Rukia is really older (she have decades, no years of life), if she go to the Human World and became a human she will grow up faster...she gonna be a old lady, while Byakuya and Renji and the others Shinigamis will be young. Futhermore Ichigo sister's, Yuzu, can't see ghosts, so if he became a Shinigami he will lost her sister. I have a really big deal with this
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