I'm not sure what novel you're referring to. However, according to the information you provided, I can try to help you find some similar novels. If the novel was written around 2004, then it might belong to the category of fantasy novels or fantasy novels. In this type of novel, there would often be some mysterious elements such as magic, divine beasts, divine artifacts, and so on. At the same time, these novels would often have scenes of sisters or brothers, such as Xiao Yan and Xiao Xun Er in Battle Through the Heavens, Yu Wenzhou and Huang Shaotian in Full Time Expert, and so on. If you have a certain preference for the plot and characters of the novel, you can search for some similar novels on the Internet, such as fantasy novels, fantasy novels, romance novels, etc. You may find the works you like.