I just started reading a really good series called Max Lovely! by Kurahashi Erika. It's basically about Airi and Taki, the two most popular students in the school. Don't get me wrong though, that doesn't mean this manga is an "opposite attracts" manga. Taki and Airi became friends when they were younger because of a rock-paper-scissor game. That game went on and on because they kept getting draws, from then on, the two became very good friends.
School life is great and normal until strange things begin to happen, they know it's the work of "F" but who can that be? As the story progresses, Airi and Taki's friendship eventually blooms into love. It's a very cute manga, you should definately try it out.