Haitang was killed by Yagyu Piao Xu in " The World's Best " because she had a conflict and dispute with Yagyu Piao Xu, resulting in a fierce battle. In the battle, Haitang was seriously injured by Yagyu Piaoxu and eventually lost her life. According to the plot of the novel, there were many misunderstandings and contradictions between Haitang and Yagyu Piaoxu, and Haitang also thought that she was right. During the battle, Haitang tried to use her own power to protect herself and the people around her, but Yagyu Piaoxu thought that Haitang's actions were wrong and attacked her. After Haitang was attacked, she fell into a coma and eventually lost her life. Therefore, Haitang was killed in " The World's Best " because she had a conflict and dispute with Yagyu Piao Xu. In this battle, she was seriously injured by Yagyu Piao Xu and eventually lost her life.