He was once able to fly.
He was once one with the clouds; he was once among the other birds. There was no greater joy than spreading his wings. Though he was free in the sky, he was chained to his emotions. He was cursed.
But now he was human. He was no longer a bird drifting among the slowly moving cotton candy like clouds of the sky. He no longer had his wings. He was human. But being human means free will. Being human was truly freer than being a bird.
A girl came crying to him. Don't abandon me! I cannot afford to lose you... Seeing her cry hurt him, deeply; he was overwhelmed with guilt. How could he leave a girl crying like that? And this was no ordinary girl; this was the girl who controlled his fate as a bird--this was the person who, no matter how many lives he lived, he would always come back to; an endless chain. She had lost this bird, and she was about to lose this human. She could not afford that. And so, his first choice as a free man was simply to clip his human wings.