The final episode should be allocated to the FL's original face. The FL should be allowed to have her own identity i.e. own face back. The FL and the ML must look for someone to reverse the original face back to the FL. If not, can the ML accept the face of a woman he never had the feeling for and sleeping next to a woman's face he had no feeling? Can the ML face a woman's face he does not love daily? So the ending of this drama is reasonable.