She sat up straight and looked towards him, as if trying to see him through the blindfold, "But-"
He grasped her jaw with his free hand, pushing her back against tank, increasing the pressure and speed of his thumb pad against her most sensitive spot. "Shut up and do it."
With that grip and those words, delivered in a harsh, commanding tone, subspace, already flirting around the edges of her consciousness, hit. Everything about her softened, accepted. Her chin tilted up and her head dropped slightly to the side, opening her throat to him, as her shoulders eased and her hips thrust towards him.
Submission held in his hands, he rotated his grip on her pussy. His active thumb remained over her clit but now his palm cupped the swollen labia and his index and middle finger delved into her wet pussy. As he tightened this grip, stimulating her inside and out, the rush of urine restarted.
Hot, so hot, as it filled his hand, pouring over the sides and down. Pressing from within, the stream pulsed in tandem with his fingers' movements on her deep G-spot. She writhed slowly through those last seconds of her pissing, grinding her mound against him, straining her thighs wide and almost seeming to hang from the hand at her throat.
As the last spurts of urine dripped out of his working hand, he heard the moaning drop in tone, become more like groans of pain, more rhythmic, ripping from her and he knew that she was close. Very close.
"P-pl... yes... please... oh f-f-fuck... please let me... Sir... Sir... please!" He watched in near awe as she struggled to drag the words out. As is from a deep well they came, raw, barely formed, animalistic. A woman with all civility stripped away by her desperation to cum, absolutely naked to him in every way, leaving nothing but her submission and need.
He shifted up on his knees, now gripping her, holding her, supporting her with his one hand tight in the hair at the nape of her neck and his other hand keeping that violent, perfect rhythm inside and outside. His lips at her ear he whispered, "Cum for me. Cum hard for me. Right NOW," and bit deeply into the curve of her neck and shoulder.
And she did. So hard. Thrashing, bucking, moaning, almost screaming. Only his three point hold, nape, neck and cunt, kept her from falling to the floor. He felt, for only the third time, that gushing cum, ejaculating all over his hand and wrist and his fingers inside pushed harder, over and over, milking it from her as her cunt spasmed around his fingers.
A minute, maybe two passed, and her groans turned into higher pitched whimpers and he slowed his fingers, easing her through the aftershocks as she trembled all over, gasping as her cunt clenched, the last remnants of her titanic orgasm shuddering through her.
Her whole body seemed to melt and become boneless and he stood, pulling her up against him, one hand gripping her ass, the other around her shoulders. He rocked her limp body, as if consoling her and she sighed with her head on his shoulder. "Thank you, Sir." So soft, barely heard.
"Oh sweetheart, thank YOU. You are such, such a good girl."