|It will be Arata since the characters resemble Hana Yori Dango. (one of the best shoujos imho)
Going off of that manga you already know
Spoiler (highlight to view)
she is going to be with Arata (tsukasa) in the end, but she will go out with and have feeling for the other guy (who resembles Rui)
hopefully it will be just as long, but it will make me lose eyars off of my life waiting for them.