Idk how to explain this. A historical bl, a relationship between master and disciple. The MC transmigrates into the masters body. So the previous owner of the body tried to damage and destroy the sipirt root of his disciple, so he hides in a icy cave. After MC transmigrates he went to find the ML and gives him medicines, after this the ml is suspicious of the MC cuz he is a regressor. I Don't remember the story properly but this is how the story starts ,