A BL fiction about how a boy entered the imperial harem to replace his sister and end up having the Emperor fall for him

After a Crown Prince, the next challenger for Jing is his very own son. Xuan Yuan Feng. If Huan Shu Cheng with his outstanding character failed to charm the getting more and more refined Lu Cang, will Jing's son who inherits Jing's brilliance and outstanding beauty succeed? However, unlike Shu Cheng who only aimed for Jing's lover, his son intends to take everything from him. This will be the final series for my long fanfiction. Thank you very much for boarding with me in Jing and Lu Cang's adventures' ship. XD

Another beautiful powerful Prince is attracted to Lu Cang. Who will Lu Cang choose? The gentle Prince who will never mistreat him, or his cruel lover who seems to take delight of his pain? What is Jing reaction?

My First Fanfiction of HHYL.