I find so many "What If"s in this show. This is one of the aspects of the show that I find completely intriguing. Just take a moment to think about all the events that occurred. (I'll be mingling anime happenings with manga) What if the Koishikawas and the Matsuuras never met on that ship? Would they still try to seek each other after so many years? Their jealousies and anger had faded long ago, and their love was slowly turning into a kind, peaceful family love instead of that passionate love. If they hadn't encountered each other on that cruise in Hawaii...Yuu probably would have never met Miki. Or if he did, they wouldn't have had as much contact as they do living under the same roof. And what if Miki and Ginta were going out when her family moved in with the Matsuuras? Would Yuu still take Miki from Ginta? Or would Miki and Ginta's relationship be too strong?
In the anime, if Anju had never left Yuu, would Yuu have fallen for her? She does like Yuu more than just a friend, and they were best friends in sixth grade (seventh too?) when Yuu went through his traumatic period after discovering the secret about his real father. Anju remeets him too late, and he is already with Miki. But what if they had met before Yuu's parents divorced and remarried? ..it's an interesting thought. Would Yuu have still felt the same way about Miki with Anju around?
Then the huge question..what if the manga-ka really made Yuu and Miki half siblings? She originally did plan on making them remain related, and they never got back together after they realized the truth. Miki and Yuu resolved to live together (though they could never marry and have kids, etc) but they're young...passionately in love..what would happen once the years go by? Would they regret having stayed together and having this *forbidden* relationship? How would their parents have taken it? Would they have approved? After all, the entire mess began because they did not tell the whole truth to Yuu and Miki from the beginning.
There really are a lot of "What If"s concerning love. If events had not gone the way they did, Miki may have found a different type of love with Ginta (or Kei-kun), and Meiko with Miwa if she had never fallen in love with Namura. Different, but still satisfying?