"I didn't understand what I felt but I do have regrets..I regret what I did to you. I would change it if I could but it is impossible. All I can do is try to make up for it now somehow."

Which is still a mystery to him. He doesn't know what it will take but he is willing to do anything. But he also doesn't want to force himself on Xingchen and so he withdraws his hand so that the man can leave if he wants to.