“A close binary system. Stars, you know. Stars are rarely ever alone.” His voice got funny. “Stars can come in clusters, but they most frequently come in pairs. A binary system.”
“Oh.” It was nice to think of Bird and me like that, twinkling pretty in the sky.
“Sometime stars in binary systems orbit each other really closely, much closer than normal. That's why they're called close binary systems. And the stars with less mass orbits its companion, which has more mass.”
“And more gravity,” I pointed out.
Eugene grinned. “Sometimes these two stars orbit so closely that they transfer matter to each other.”
“Parts of them fly off and get pulled in by the gravitational pull of the companion star. And vice versa. Each star is changed by the other.”
“They each have parts of the other?” I asked.
“Yup,” Eugene said. “And because of that, the stars' compositions change, as well as how they develop in the future.” he craned his neck up to the sky. “It's like with you and Bird. He's in you. And you are in him, wherever he is.”
- from BIRD by Crystal Chan