The next day Luke was waiting, wide-eyed and terrified, for Vader. When Vader entered his cell he got a surprise as the child flew to his neck, sobbing.
Vader carefully pried the boy's fingers off his neck. Luke looked up at him with huge, watery eyes. Vader loosened his grip on the boy's wrists and Luke pressed against his chest plate again. Gathering the child's little legs in his arms, Vader carefully sat down on the cell floor.
He carefully rocked the sobbing child for several minutes, until the boy could talk again.
"What happened, Luke?"
Luke lay back in Vader's arms, wiping tears out of his eyes, "They-they said that you had given up on me. They said you weren't coming anymore. They swore that they were going to break all the bones in my body, and without you there'd be no one to care."
Vader felt a kind of warmth he hadn't felt in a long time. It was the kind of warmth that warmed you from the inside out. He shivered a bit as he realized that he was feeling love for the boy who had been so terrified by the prospect of losing him.
"I won't let them do that to you, Luke. I promise. I can't stop them from torturing you, but I won't allow them you break your bones."
Luke hiccupped and nodded, "I knew you wouldn't. I knew it. I just- I was so scared. Promise you won't let them."
Vader felt the warmth again and he pressed the grill of his mask into the child's hair, wishing that he really could smell the boy's scent and feel the overlong blond hair on his nose. "Silly boy," he murmured, "I already promised."
Luke relaxed in Vader's arms. Vader stroked his hair and let him cry. He wrapped his cape around his little rebel.
Luke felt strange clinging to Vader. Part of him screamed that he was being unfaithful to his father, but another part said that if Anakin had been any kind of parent at all he would just want Luke to be happy. It felt strange to sense the happiness that he was bringing Vader. It was odd to know that Vader had chosen one person out of the entire galaxy to love and that was Luke.
Vader let Luke cry in his arms and stared at the boy who was so unsure of where he stood in the galaxy and even in the Force. Luke could be so full of resentful anger or such unconditional love. Luke was trying to hide from his humanity so that he could be a good son. He really was the perfect son.
Vader considered asking Luke what lucky person had been his father, but he was afraid that Luke would withdraw again. He was also afraid that the father might have been one of the people who had betrayed his especially spectacularly. If I don't ask him that sort of question he is more likely to open up on his own if he wants to.
Luke nestled under Vader's arm. He had been so frightened that Vader would decide that he wasn't worth loving and caring for. Yesterday he had pushed Vader away, but now he valued every moment in the older man's arms. He could feel himself shivering and he could feel every patch of particularly filthy skin. Vader didn't mind. That meant everything to Luke.
Vader looked at the boy's matted, bloody hair. He felt that he should do something about Luke's discomfort. Letting him go will be a challenge. I wonder if I'm up to it. I wish he was my baby. I wish Padme were here to help me decide what to do. She would love Luke. Maybe I should take him in. I could give him a home and all the possessions and love he could ever want. Darn, this isn't working at all. I'm supposed to be teaching myself to let go, not trying to take another burden. Oh, Luke. You've made my life even more confusing than it already was. Congratulations.
Luke made a soft sound, partly the coo of a dove and partly the purr of a happy pitten. Vader smiled down at his little burden. Luke sensed Vader's happiness and smiled up at Vader. I don't think either of us knows how important this is. I love you, Dad.