Hell, if we're talking about such relationships, might as well throw my $.02 in.
Keitaro/Kanako I have no problem with. They're adopted siblings, no genetic relation. Well, correction, I do have a slight problem with it, as Kanako is the creepy stalker type, and that makes me uncomfortable. It's like"Fatal Attraction". *shiver*
(Kanako: I will NOT be ignored, Oniisama!)
Rei/Shinji can be done, and it's okay with me. Considering her Angel DNA, I think she's probably genetically different enough that the relationship doesn't qualify.
Now, the Naruto things.
This is just an aside, but I think it's hilarious that, before the timeskip, nearly all 'shippings are by nature either lolicon or shotacon. :snigger:
Anyway. Naruto/Tsunade is fun, but it stretches my suspension of disbelief. She thinks of him as "younger familiy member", he thinks of her as "older woman who might be kind of a mother figure". It's sure not incest (at least I think it's not, unless some fic ideas turned out to be true), but it's not conducive to romance or sexual attraction. Not saying it can't be done, but it sure ain't easy.
Naruto/Shizune. Works well enough for me, even if it is still pretty shota.* She's not too much older, is cute, and has shown a decent amount of respect and affection for Naruto. He does call her "neechan", which is a staple part of younger man/older woman pairings... ^_^ And, it happens to be one of the obvious pairings in this ficbit.
Naruto/Tsunami is pretty much the same as with Shizune in my book. I think the two are about the same age (Shizune 28, Tsunami 29), and she seems to be past the grieving stage of widow-hood. Naruto's friendship with Inari isn't so much an issue to me, so long as Inari doesn't catch them doing the H or fighting.
(who am I kidding, that helps it for me.)
Edit: Oh, and I forgot about asking this before. I remember reading on a newsgroup that Haruka and Keitaro are cousins, not aunt/nephew. He calls her "bachan", which technically means "aunt", but is used for most older family members who aren't close enough in age to be called "neechan" and aren't the speaker's mother. She hates that because it makes her feel old.
Can anyone support or deny this one? I've been looking for over a year, and can't find any more information.