Long enough to make him beg

Time had slowed to a crawl. Marcus was frozen in place, that horrible, wonderful tentacle still working its teasing way in and out of his butt. The sheer aching need to cum was all he could think about. His dick felt so hot and swollen, throbbing agonizingly with his heartbeat. Even the tingling pressure in his butt had grown near unbearable. Every time that soft slimy thing drove itself deeper into his guts he felt himself teetering on the very edge of climax, but then it would just draw back, slowly and gently, like it knew exactly how to make sure he didn't cum.

The silver goblet was about half full with white pre-cum, more dribbling from the tip of his throbbing dick, but Mistress had made no move to stop this. Instead she just sat on her throne, watching him with that same sadistic smile. If Marcus could speak he'd be babbling and screaming at her to let him cum, if he could move he'd be pounding back into the tentacle with all his strength. He knew he wouldn't even have to touch his dick to spurt, and it felt so horribly sensitive right now he didn't want to try. Just his butt would be enough, if she'd only let him move!

The horrible thought that his new goddess might be waiting for the cup to be full sent Marcus tumbling into utter despair. He couldn't imagine being kept like this that long. He'd go crazy! She knew that right? She had to know!

Suddenly she raised her hand, and just like that the tentacle stopped, buried to the hilt in his poor aching butt. The goblet moved, gliding through the air to her waiting fingers. Marcus watched through a haze of awful need as she lifted the cup to her face and swirled it round, staring into the contents with glowing purple eyes. Then she smiled thinly, and the satisfaction on her face filled the young prince with trembling warmth, enough to sweep away all his horrible frustration. He'd done it!

"Yes, this should be more than enough." She purred. "Well done, apprentice, but I think we'll have to do this rather more in future. Repeated stimulation of that area should make you capable of producing valuable reagents at a much higher rate." She released the goblet again and it hovered in the air beside her. Another flick of her wrist and a bowl appeared in her hand, the same glistening silver and etched with the same strange markings that made Marcus' head spin just trying to look at. "I suppose I should also take this chance to harvest some of your semen too." Mistress continued, releasing the bowl and letting it move down to that same place just below the young prince's dick. "Or, I could just end things here, without letting you cum at all." Her smile widened, baring her perfect white teeth. "That could be amusing." Marcus would have screamed in horror at the thought, if she'd just let him speak. She couldn't leave him like this! Sure, she was so wise and kind and perfect, but that would be just too awful! "I'm going to let you speak in a moment, apprentice." She breathed, her sweet voice low and hungry. "If you can beg pretty enough, I'll let you spurt all your valuable royal seed into this bowl. If I'm not satisfied, then we'll just continue milking you for a little longer, I think."

Marcus **** himself to focus through the awful, waves of white-hot need. If he couldn't control himself now he'd just start babbling or screaming, and he knew that wouldn't be enough to satisfy her. No matter how unfair this felt, Mistress wanted it, so it had to be right! She nodded once, and he took in a sharp, gasping breath, knowing he could speak again at last.

"Please, Mistress, let me cum!" He squealed, his voice a high-pitched, trembling whimper. "Please, I'll do anything! I need it! I'll give you as much as you need later! Just please let me!" He stared at her, begging with his eyes and his face and his whole frozen body. She let him hang there in suspense for a few agonizing moments, then she smiled again.

"Very well, apprentice, you've convinced me." She murmured. "You may cum, but remember all those pretty promises for the future, okay?"

"Yes Mistress, thank you Mistress." Marcus replied, silently promising himself he would. Just like that, the tentacle started moving again and he moaned in hungry delight at that delicious stretching feeling as it drove into his butt. It was moving much quicker now, and pounding much deeper inside him, filling him up in a way that sent waves of trembling pleasure through his aching body. Girly little yips and squeaks escaped his lips. In just moments, he felt those white-hot feelings sore to a peak of bliss.

Marcus screamed in pleasure as he came, his mind washed clean by that wave of utter satisfaction. This wasn't anything like those times he'd clumsily rubbed his little dick in bed at night. His whole body seemed swept up into the orgasm. Suddenly able to move, he collapsed like a limp doll, his legs and arms twitching and thrashing. The tentacle was still pounding him, each hard thrust sending another wave of heat flooding up through his core. His dick was still cumming, still spraying thick white cum into the bowl every time that soft, slimy, wonderful thing slid against the throbbing walls of his butt.

At last, he felt it all slowly fade. It seemed to take a long while, but when he could think again he found himself lying on his side on the cold stone, his muscles aching and twitching. He felt exhausted, utterly drained. Just in front of his dick, the bowl was full of more pearly cum than he'd ever spurted in his life before. His trembling gaze moved up until he found his Mistress, still sitting there on the throne with her long legs crossed. Lost in warm feelings of satisfaction, he felt his love for her swell painfully inside his aching chest. No-one had ever made him feel that good before.