Like kim shin, Bai Qi is a supernatural being who has lived for a very long time helping some of the spirits. Many years later he meets the reincarnate of his lover who is also silly but cute, like Ji Eun Tak . Also the relationship between Bai Qi and Yang Jian is similar to that of Kim shin and the Grimm reaper in that they are enemies but do not go as far as killing each other although I am not sure what happens in the future.. All in all, the similarity is in the reincarnation, spirits/ghosts, romance, frenemies, rich man poor woman and the male lead wanting to protect the female lead while being in denial of his own feelings for her.. Not to mention the similarities in Kim Shin's sword and Bai Qi's umbrella. Awesome story so far..