Clotho of the fates weaves the thread of life. But in modern times, gods and goddesses have ceased to exist in their own plane and instead Chloe lives with humans. And because she has lived with humans for so long, she has forgotten who and what she is. But her powers still work and birth still depends on her.
The people who are born are inspired by her moods. Say for example, if she's feeling a little violent, criminals are born. If she's feeling creative, artists are born, etc.
Ares is a god that wants to wipe out human existence. Anyway, he kidnaps Chloe. If she can no longer spin threads, humans will cease to be born.