" Please. Do this for me one more time and I’ll give you…” A thought struck her and she let out an exalted laugh. “I’ll give you my firstborn child!”
He balked. “What?”
She gave him a chagrined smile, a helpless shrug. And though the words had been said in jest, she was already beginning to wonder.
Her firstborn child.
The likelihood that she would ever conceive a child was so minuscule. Ever since the fiasco with Thomas Lindbeck, she’d felt resigned to a future of solitude. And given that the only other boy who had captured her interest was dead…
What did it matter if she promised away a nonexistent child?
“Assuming I live long enough to birth any children,” she said. “Even you have to admit that’s a good deal. What could possibly be more valuable than a child?”
He held her gaze, his expression intense and, she thought, just the tiniest bit saddened.
Under the soft fabric of his sleeves, she imagined that she could feel his pulse. But no, it was only her own heartbeat, fluttering in her fingers. And in the sudden silence, she caught the tremulous rhythm of her own shallow breaths.
The moments ticking by, too fast.
The candle flickering in the corner.
The spinning wheel, waiting.
Gild shivered and tore his gaze from her face. He looked down at her hands, the pried his arms away.
Serilda released him, heart sinking.
But in the next moment, he’d taken her fingers into his. His head lowered, avoiding her gaze, as he wrapped his fingers around hers.
“You are very persuasive.”
Hope skittered inside her. “You’ll do it? You’ll accept that offer?”
He sighed, the sound long and drawn out, as if it physically pained him to agree to this. “Yes. I will do this in exchange for…your firstborn child. But” —his grip tightened, squashing the jolt of euphoria that threatened to have her throwing her arms around him— “this bargain is binding and unbreakable, and I fully expect you to stay alive long enough to fulfill your end of it. Do you understand me?”
She gulped, feeling the magical pull of the bargain. The air pressing in around her. Stifling, squeezing in against her chest.
A magical bargain, binding and unbreakable. A deal struck beneath the Chaste Moon, with a ghostly thing, and unliving thing. A prisoner of the veil.
She knew she couldn’t really promise to stay alive. The Erlking would have her killed as soon as it pleased him to do so. And yet, she heard her own words as if whispered from a distant place. “You have my word.”
The air shuddered and released.
It was done. "

― Marissa Meyer , Gilded (Gilded, #1)