The devil learns love.
How could anyone love him when he himself hated his being, hate to an extend that it turned him into a grotesque demon like creature. He was made by the hands of the all-powerful divine God and yet his free will had turned him into a being that looked like it was made of burned and rotting flesh. He was-is an angel. Wasn't he supposed to be all goodness, all beautiful, then where had these parts of him come from? these terrible bits and pieces of his soul that she a mere human couldn't even love. Humans said that they had soul mates, one someone who was made for them, some claimed to fall in love with the soul of the person and not the clothes of flesh they wore. Where was her love then? she had responded to his charming good human looks, yet she had turned tail and disappeared when one of his faces had shown itself. She had plotted to kill him, send him back to the place he loathed the most. She had forgotten everything that had happened between them, their friendship, their partnership, their trust. She had thrown it all away, she had forgotten how he had bled when a thousand bullets had pierced his wings when he had tried to save her from Cain.
Humans were vain like that, easily manipulated by appearances and he didn't blame them. They didn't have endless supply of time to learn about soul. He himself was unaware of the secrets of the soul but he knew of their endless desires and through desires it was easy to judge hence he was yet to figure out her. Was she a pure soul or a corrupt one he knew not.
He loved her though and his love for her was pure, the only thing left of the divine. Snowy and celestial like his feathers, all healing and beautiful. His love for her was selfless and it was the first time in his endless existence that he had loved. And this love he would keep in his immortal heart, its flame flickering to keep him burning till his end. He didn't want to ruin his love for her, it was a gift, not from his father but for himself for him, he needed to protect it at all cost. The pain that spread from his heart was the sweetest agony he had ever felt. And for that he needed to be away from her.
Her betrayal had done nothing to his love, it had remined the same, untainted and heavenly, sweeter than the sweetest apples of the silver city. She had claimed that she loved him, he could take that and remember her by. He knew she didn't exactly mean it, humans were known to throw around the three little words when it benefitted them, she was just trying to not lose her partner and friend. How many women he had come across had done just that, claimed to have loved a friend out of fear of losing them. He didn't need her pity. He didn't need her love even but he needed her to be well. He needed her to be loved, cherished and be happy. He needed her to have a full life away from all the dangers he had put her through.
He knew the gates to the silver city would never open for him. He knew he would never see her beautiful face in her lifetime again but he could hope. Maybe one day his father would let him slip through the doors to see her when she came. Maybe Amenadiel would one day visit him and bring news of her, of the life she would live, of the children she was yet to bear, of the criminals she would put behind bars, of her amazing adventures that he knew he would never tire of hearing. Maybe Amenadiel could give her a letter that he could write to her if that were possible.
He had hated his father for everything that had happened to him, yet he was thankful today, for putting her in his path. He was thankful for the love he had experienced and all the hurt that came along with it. It had changed him. He finally loved his father for it. The Devil had finally learned to love.