Bo Bing is a medical student who went to Japan to pursue further studies, a young girl in a foreign land she met a senior student, Ye Zheng Chen who is also an aspiring doctor in the same university as her. They shared some common factors, become fast friends, and gradually fall in love. Ye Zheng Chen loves Bo Bing deeply and affectionately calls her ‘lass’ instead of her name. However, Bo Bing later discovered that Ye Zheng Chen is in fact already engaged to another girl and was upset she is being lied to. Ye Zheng Chen tried to explain his difficulties but Bo Bing fled back home before he can tell her the truth.
Three years later, Bo Bing’s fiancé is being charged and she is told that only Ye Zheng Chen has the ability to help her. Bo Bing is therefore being forced to trade herself to Ye Zheng Chen in order to save her fiancé. She also learns the secret that Ye Zheng Chen has been hiding from her since their days in Japan three years ago…