Kaede is Minoru's sister that Yuzuki is based upon. She was always there for him, especially when their parents divorced. She was said to be always smiling and took care of Minoru. Very little is known about Kaede herself, except for what Minoru or Yuzuki says about her. Kaede died from an unknown and sudden disease with Minoru holding her hand to the very end of her life.
Editor's Note: Some people say that she is the same as Kaede Saitou of Angelic Layer. One even says that the Chobits manga has a drawing of Kaede, with a few of her friends, and each of them is recognizable from Angelic Layer.