A/N: written for Trope Bingo Round 12: Indecent Proposal.
When he heard her footsteps, Blackheart knew she was ready to make a deal. Or close enough that all she would need was a nudge. He leaned back on the plush leather couch, tilting his head and studying Grace as she walked into his new abode. "So the prodigal queen returns."
He really is a sadist. Blackheart had made the offer, not her; he'd made the terms and conditions, the catch twenty-twos and fine print. Yet still he acted like it'd been her idea, that she'd come to him and offered him certain favours in exchange for power. Grace wasn't sure whether that offended her, or if it was a sign he'd finally come to realise he couldn't seize the throne with only a few elemental spirits.
"Have you made your decision?" he asked, carding his fingers through his hair. As his hand moved, hair became tendrils, and the pale washed-out skin of his human form turned a deep midnight blue as a ripple moved outwards. "There are many others who'd jump at the opportunity to kill—"
Grace seated herself on a wooden chair opposite him and said, "you talk too much for a King."
"Is that a yes?"
"I haven't decided."
"Then why did you—" His eyes flashed with anger, midnight blue giving way to sickly milk-white, whilst Blackheart transitioned between forms once more. It was much easier to communicate with humans when he looked like them. They could see the emotion in his eyes, understand the threat that faced them without struggle. "Did he send you here? Mephistopheles, or the Rider?"
"You came to me, offered all this to me. I'm not a spy, you stupid son of a bitch." She was taking her time, that was all. The offer hadn't just been for power, for some magic pen she clicked to become a Sailor Scout. He'd said 'transformation', and that it required the permanent loss of her humanity. "I'm just trying to figure out what kind of monster I'll become."
"Who said anything about monstrousness?"
"He killed my father, my brother, all with that stare of his. If becoming a monster is what it takes to destroy the Rider then that's what I'll do."
"I still haven't heard an answer, Grace."
He wanted an answer, he wanted power, wanted his father dead — and he wanted it all now. Patience really was not his forte.
She looked at the ground beneath her feet, clenching her hands as memories seemed to stir in the back of her mind. Screams, crackling flames, the sound of a motorbike driving away. It was called the 'penance stare', Blackheart said; no one survived it. Grace wiped stray tears away with the sleeves of her jacket then nodded, her expression both sombre and angry. "Yes."
"Say it again." Blackheart stood, crossing the gap between them in two strides. He lifted her head gently, held her gaze for a beat longer then drew her up with one hand. "Three letters."
"Yes," Grace hissed. She gripped his forearm, relishing the sense of stability his body provided. Her hand trembled slightly but the rest of her was still, calm. "Y, e, s."
"Then come with me."
She stood, looking around as if Wallow or Gressil would suddenly rise from the ground. "What?"
"The contract must be signed, the transformation begun." And there was the small matter of payment. He smiled, drawing her close with his free hand. Hadn't he told her what would be required? Blackheart was certain he'd gone over the details ... in his head. "I'm not the Devil. I can't just expend all my power and turn you here."
"Why not?" asked Grace. Something warm caressed her skin, drawing her gaze down. Flames licked at her skin, turning it white as burnt charcoal. The smell of fire and heat followed and with it came pain. She cried out, digging her fingers into his arm, clutching at him when her knees began to buckle. "Is that—"
"This is how it begins. Your soul burns away while we make something new."
"And that involves—" One moment she was standing in the abandobed house, the next her head landed against a pillow. Grace shuddered at the feel of the mattress beneath her, the silk sheets smooth against her skin as they twined around her arms. The warm scent of brimstone wrapped around her, like someone had simultaneously lit a thousand matches and wafted the smoke about the room. "Ohh."
"It distracts from the pain." When he looked in her eyes, Blackheart found himself staring into a burning pit of sin. Every wicked thing that had crossed her mind was reflected back at him. Promises of absolutely delightful corruption and lust. "Now..."
She lifted herself, reaching for the strap of her bra only to find Blackheart's hands already there. The clips were undone, her shirt buttons popped, and then he was pressing her down into the mattress, mouthing at her neck. Oh, please, yes. Pants were shoved down to her ankles, burned to ash when they wouldn't come off; black lace panties split on each side then tossed away like garbage.
His mouth blazed a trail up her legs, her thighs, towards the heavy throb and slick heat of her core. Each swipe of his tongue matched the black flames tasting her skin, penetrating her being, purging her soul from her corporeal form. And every time she thought he was done, Blackheart found something else he wanted to taste. Something else that needed to be burned away or destroyed.
By the end, she was limp in his arms, breathing shallowly and slowly, waiting for the pain to subside. Waiting for him to scoop her up, carry her to a bath and wash the ash away. From head to toe, dirty white flecks coated her skin, made her look like some kind of spirit from the stories Mama had told her as a child.
"We've still the rest of the process to go, my queen," he whispered, caressing the smooth expanse of her neck and bare shoulders. Blackheart cradled her against him, one leg laying over hers, arousal resting against the curve of her ass. "But I think you're going to enjoy it even more."
There was still a ways to go? Grace nodded slightly, wiggling back against him. Already she could feel something at the edge of her mind, a kind of presence that flowed around her like a stream. Power, she thought, and smiled. Soon enough she'd dip her fingers into it, but for now, Grace wanted nothing more to enjoy the rest of the process — those deft, skilled hands of his, caressing her, stroking, causing sensations she hadn't felt in many years — and the quiet solitude of Hell.
"Soon," she murmured. "Once I've had a chance to gain my strength back."
The future King kissed her shoulder blade and smiled. Of course. She was going to need all of it when they destroyed the Rider. "I think I can provide some assistance with that."