They should never have met.
Each one of them lived in different parts of the world. She lived in the light, an ordinary existence while he kept to the shadows, the underworld.
But one fate encounter brought them together and no matter how hard they tried, they couldn't deny the pull they felt towards the other.
They thought they could make it casual, to take comfort in the other's bodies and then walk away. But any hope of that ended when the strip turned blue and if he knows anything about his world; once you're in it there is no leaving.