There was no specific chapter in Hua Qiangu's novel that said that Bai Zihua only left a little proof of his love for her. This question was not explicitly mentioned in the novel, nor did it leave any relevant clues. However, according to the plot of the novel, Bai Zihua did stand up for Hua Qiangu when she was in danger and sacrificed his life for her. This was a very touching plot and one of the classics in the novel.