Gu Enyu is basically a fictional character. Although he is not a completely fictional person, he is just a young lover of Sai Jinhua who has not left much materials and information. Looking through the available historical materials, I only mentioned one or two sentences when interviewing Jin Songcen, the original planner and author of "Evil Sea Flower": "... Guangfu Gu Heng was like a gentleman, and he was very close to Sai Jinhua when he was young. When there is something interesting to say. " "Gu Heng is the happiest official in Beijing ..." These words have been ignored by many people who study Sai Jinhua, but Zhang Xian skillfully grasped this fragmentary record, invited this Gu Jun out of the dust of history, and made a fiction, transformation and sublimation to make this character stand out and make it run through the whole play. Let him add luster to Sai Jinhua's life, and be more closely linked with the changes of the country, so that Sai Jinhua's growth and development have a more real and convincing basis. In addition, Gu Enyu and Wei Sihuan are described as friends of life and death, so the continuation of love for Sai seems natural and solemn, and Wei Sihuan's image is also enriched, which makes the love between Wei Sihuan and Sai Jinhua show a rare grandeur and nobility in her life, which has become the reason why she paid special attention to it until her death. Gu Enyu's characterization is undoubtedly a creative success.