Her Disguise.

Lin Man Ge, a righteous and smart medical student, sneaks into the Lu family to avenge her friend Lan Lan's bizarre and tragic death, and becomes the eldest son's fiancee. However, she is discovered by the fox-like second son Lu Hao Ran, and a series of abuses and counter-killings begin. As she gets along with Lu Hao Ran, she is attracted by his sincerity and justice under his disguise. These two go from suspicion to trust to love, and finally find justice and the truth.