Female Doctor and Secret Guard

She was an orphan abandoned by her family. She was picked up by someone by chance and acquired medical skills. From then on, she began her life of treating diseases and saving people. He was a child abandoned by the clan, and was later trained as a secret guard. He lived in darkness from then on, and then she appeared. She was a light in his life, illuminating his whole world. She kept saving the same person, but unexpectedly she got entangled. In his opinion, she not only saved his life, but also his heart.