He walked among stars.
He had been born as Tabris, but only really lived as Kaworu. He had never understood the difference between existence and life before he used that name, and met the one who made it mean anything at all.
The angels liked to think that they were superior to the lilan, with their immense power and intellect. He supposed that, in those senses, they were. However he had come to realize that those things were insignificant compared to what humans had mastered.
Life.
The angels knew only how to create and destroy life. The humans could create and destroy, but in between they formed bonds and ideas and endless possibilities that Kaworu saw as the highest form of art on any of the worlds he had seen.
He had never truly understood why Shinji saw himself as so unimportant. He was, to Kaworu, the very embodiment of all the possibilities of humanity. His soul so strong that when it's will met Kaworu's, it created a seemingly endless chain of worlds and times a realities, unconsciously searching for the one where he could find peace.
(Kaworu was grateful for this, even though it was the cause of thousands of times more pain)
Kaworu, when born as Tabris, had been created as the angel of free will. A silly title, as the terms 'angel' and 'free will' in the same sentence created an oxymoron. To be an angel was to be enslaved to the decisions of the commander, to god. The title he had been given by the angels was only ever relevant after he came in contact with humans.
Of course, nothing could ever really be that simple. In exercising his free will, he had allowed himself to fall in love. A very dangerous thing to do, as he soon learned. He has been foolish enough to think that he would be able to stay with his beloved, and ignore the task set out for him by the angels. Of course that hadn't worked out, and the pain of knowing that he was hurting Shinji greatly outweighed the pain of being crushed by the Eva.
Kaworu realized that he really was foolish. After that first death he allowed himself to attach to the pull of Shinji's being, and be taken to another time line. He wasn't all that surprised when he died again. And again. And then again countless more times. He knew he was foolish, because if he really tried he could stop the time lines, he could stop entering Shinji's life. But he was foolish and selfish and so, so in love. He was addicted to the relief he felt every time he saw Shinji in a new universe. Every time he saw the boy's beautiful eyes widen in confusion when Kaworu was kind and patient towards him.
It was almost funny, in a sick sort of way. He was one of the most powerful beings in existence, and he was being destroyed by a simple human. But really, if he was being honest, he would die a thousand more times if it meant he could have a chance of being with Shinji. Of being happy.