There's one line in anime that I hate. Whenever I hear it I cringe and just know there's going to be a "oooh even though this isn't technically what I think it is, it's still wrong" moment.

Even though we're not related by blood...Random Anime Girl

Oh, Christ! I can't go on! This is bananas!

I don't see what the whole obscession is in Japan with cousins. I read somewhere that cousins dating is seen as an almost comedy in itself, like purposely mis-matched couples in sit-coms. But I mean, come on! It's in almost every romantic comedy anime going. Harems are now boiled down to:

The real love interest - Will have the second biggest boobs out of all of them and is either bashfully quiet and sweet or violently in denial.

The lust/secondary love interest - Will have the biggest boobs and be the biggest flirt. More often than not is also quite a-female-dog.

The emo - Has problems which the protagonist solves by not being a complete asshat towards her.

The tomboy - Has the smallest boobs and thus the shortest temper.

The child - Shoehorned in for all the sick lolicons. More than likely good at housework. Having a twin or identical best friend is optional, but recommended.

The distant cousin - Is either not related by blood, or is a second-removed or...something. Either way, will inevitably say the above line and make a really awkward scenario mid-late through the series. In rare cases can be replaced by a step-sister.

The housewife - This one is entirely optional. Is always dead cheery and good at cooking, most likely has a bust rivalling the secondary love interest.

However, this doesn't stop me from watching harems, as a lot are dead funny. Love Hina will always be the standard, in my opinion though. :P