Board Thread:Speculation House/@comment-10390252-20141218201832/@comment-25396609-20150316183840

anything past 2nd cousins is fair game if i recall correctly. although, if it wasn't for the american audience japan rules (which i can best summarise with a naruto fanfiction quote) would apply. the conversation, as i recall, was something like this

Naruto: I can't date Anko, she's like a sister to me,

Kyuubi:Incest is best, put your sister to the test.

I'd worry about that quote being inappropriate, but a few people have openly shipped yangXruby at one time or another.