Yichen was an orphan and adopted by Liu Shangfeng since young. After he had grown older, Liu Shangfeng felt that he possessed talent in refining medicine, so he started to teach him some basics of medicine refining. A few months ago, one of the Fourth Princess's playmates was severely ill and visited Liu Shangfeng's place for medicine. However, Liu Shangfeng was not at his residence that day when she came to collect the medicine and the person who gave her the medicine was Yichen. Yichen did not give her the medicine concocted by Liu Shangfeng and instead gave his own medicine…
As a result, because the medicine was not up to the standard, not only did it not cure it, it had almost caused the Fourth Princess's playmate to die. Thus, Liu Shangfeng drove Yichen away.