I was just pointing out that your statement "incest is something that happens between blood relations" isn't strictly accurate, especially if we're discussing squickiness rather than legality.

I find Xander/Dawn hugely squicky - I think I gave it a 9, and its recent appearance in canon is one of the things that has made me start questioning Joss's sanity - but not quite as squicky as Buffy/Giles, which to me is the squicky-est possible relationship in the 'verse not involving blood relations because Giles is definitely a parental figure and he's even boinked her mother.