A/N: SPOV
Severus was at the height of his frustration as she had him enveloped totally. And with that, he was nearing the peak of his release. He couldn't help but clench her hair as his hips spasmed involuntarily and his usual crash of pleasure was multiplied by the fact that she had kept going.
In his experiences, the girl would pull away at the first sensation, or would stay for a second or two before reaching for a glass to spit into... but she endured like the tales of the succubus who would continue until they had every last bit of your life's essence.
She had moaned appreciatively as she realized that Severus' cock wasn't softening as she had expected.
"Did you not expect an encore? I am a Potions' Master." He pulled out his wand and detached the cuffs from each other. He cleared the bed of all his toys, and removed the cuffs from her wrists.
"You've been an extraordinarily good girl tonight, and deserve a reward." Extending his hand, she took it and stood before him. He guided her to the bed and she laid down on her back, unsure what he was about to do next.
The pillow that was under her head before was now just under her hips. Severus slithered onto the bed, spreading her legs apart and biting her inner thigh as his eyes locked onto hers wickedly.
His lips locked onto her clit and suckled it with an intensity as he slowly put three fingers into her. He smiled as her hands clamped onto his skull and her fingers seized onto the locks of his hair. As he alternated from suckling her with three fingers and using his tongue to penetrate her, he found his fingers going deeper each time.
Her flavor was heady and savory; he felt like he could stay down here for hours. Instead, he used his fourth finger inside her and loved the gasp that she made as he worked himself into her.
Shifting his weight, he crawled up the length of her body and suckled on her nipples as his hand was nearly fisting her to her bottom knuckles.
She was crying out, and the sadist within him drank in the sight of her eyes tearing up as she could barely keep her head still.
He changed the rhythm of his hand, forcing his lips upon hers and letting his tongue convey her taste back to her. He was letting her taste herself and he greedily tasted himself on her mouth.
Her nails raked down his back as he let himself lay upon her, guiding himself inside her. Locking eyes, he witnessed the look on her face as he penetrated her. He would never get tired of seeing that expression.
He pumped his hips, and found his tip pressed against her cervix. It was a pleasurable pain for him, and he repeated the slow stroke only to harshly thrust the last inch into her. Over and over, he felt her thighs quivering as she tried to wrap her legs around him.
As he quickened his pace inside her, he had one hand seized on her breast while his other was latched onto her throat, squeezing gently.
"Mmmm. Mine." He murmured, sliding himself all the way into her at a fast, deep pattern as she moaned something unintelligible to him.
Her moans intensified as his speed increased, and her gripping spasms around his cock increased as she orgasmed. The sound and sensation alone had threw him into his own orgasm, feeling himself unload within her.
He melted into her as she melted into him, boneless and fully satisfied as he curled up behind her and held the Auror against him.
It was the first time in a long while that he was able to sleep throughout the night without utilizing a potion.