He does.
She does.
That's how it is, day after day and night after night. Moon would chase her sunsets every single day and to him, that was enough. But there are special days when Moon completely catches Sun and he becomes selfish; shielding her from the earth and keeping her all by himself and that's when we look up in the sky and see a magnificent eclipse.
The Moon glows because of the Sun, for the Moon belongs to Sun as the Sun belongs to the Moon.
- END -