This chapter takes place after Chapter 19
Shirou stood across Arcueid in the dojo. It had been only two minutes since there date. In that tine Shirou had travelled all the way from Shinto to Miyama and found her in this room.
"So I must ask Arc," Shirou said his voice steady and not containing a trace of his steadily growing lust. "Why the dojo, it's not the most romantic location for making love."
At this Arcueid blushed, "I just thought if we did it in your room we may damage the floor if we get to wild. The dojo has durability runes so it won't make a difference." At this Arcueid smiled and her look of lust came to the fore again. "In here we can seal the dojo and go as wild as we want without having to worry about noise or other people bothering us."
Shirou nodded in agreement and with a click of his fingers the dojo sealed itself the door slid shut and the room was rendered completely silent and unenterable.
"Now how do we do this," Arcueid said. "I haven't done this before."
At this it was Shirou's turn to be shocked. "Really you haven't had anybody tell you about it or seen it done. Haven't you watched porn?"
"What's porn?" Arcueid asked him questioningly.
"Nevermind," Shirou said quickly. They all currently lived in Japan and he'd be damned if he let Arcueid see Japanese porn. He didn't think his body could take it.
He sighed at the thought. This was turning into SexEd. A very fun SexEd with a very attractive student however. "First thing we should probably do Arc," he started. "Is to take our clothes off."
He started quickly undressing while watching Arc do the same. She stripped off in a very methodical and practical way and somehow the sheer casualness of her taking off her clothes was enough to get him hot and bothered. "We are going to fuck," he thought to himself. "In just a few short moments we are going to be touching each other intimately and rubbing up against each other."
He felt himself harden in his pants and realized with a start that Arcueid had finished and was now staring at him. Her breasts stood erect facing him and her nipples were hard. The exotic nudity of her body caused his mind to momentarily blank before he blushed and pulled off his pants leaving him in boxers.
With absolute embarrassment he finally dropped his boxers causing his very erect penis to jump out and stand at attention. He stepped out of his boxers and threw them to the side and once again looked at Arcueid. She was fidgeting rubbing her thighs together, her eyes were fixed on his penis and her mouth was open in an "o" of surprise."
Shirou breathed in deeply and the steadied himself. "Okay," he said his voice barely more than a squeak. "The purpose when having sex is to either recreational or to have a child. We are doing it recreationally. Wait a moment." He quickly applied the concept of infertility to himself so that no accident could happen and no children could be born. He really didn't want to become a father.
He continued, "Okay, recreationally the purpose of sex is to provide pleasure for both yourself and your partner. You do this by stimulation or erogenous zones," he said stoically preventing himself from blushing any further.
He took a deep breath, "Erogenous zone for women are the breasts, mouth, vagina, clitoris and butt." He continued pushing past the embarrassment. "Erogenous zones for men are the mouth, penis, scrotum, and," at this he blushed slightly, "butt. Nipples also to a lesser extent. Got it?"
"I think so," Arcueid said. "So the goal for me is to stimulate your parts and for you it's to stimulate mine."
"Pretty much," Shirou said portraying a magnificent temporary lack of foresight.
"Okay, I'm ready," Arcueid said.
"Okay let's begin," Shirou said and then all hell broke loose.
In under a second he was beneath a very naked Arc who had immediately charged him and tackled him to the floor. She placed one hand on his chest pinning him to the wooden floor and with the other she grasped his erection. She initially pulled too much on it but at Shirou's wince she relaxed her grip and started fondling his hardness.
The sight of Arcueid dutifully attending to his erection caused Shirou to grow a bit but he ignored the spasms of pleasure that flowed through his body with every twitch of the vampire's fingers. He instead focused on the only parts of Arcueid that were in range. He reached out and firmly grasped her nipples rolling them between his thumb and forefinger.
This had the immediate effect of Arcueid stopping her ministrations to his penis. As a much more favourable side-effect the weight on his chest also loosened which allowed him to wiggle free while still playing with her pink buds. Pressing the advantage while she was indisposed he pushed her to the ground and sat on her stomach.
Grasping her large breasts he brought them together and thrust his penis between them all the while fondling her nipples. Arcueid was still physically stronger than him and if he stopped pleasuring her for a moment she would likely regain her senses and he would very literally be screwed.
Knowing this he thrust forward slowly while doubling down on his play with her areolas. With a slight application of his magecraft he used water to help stimulate her breasts. Heating and cooling the water he sent conflicting sensations to his partner in this dance they were partaking in.
"Cum, damn you cum," he thought simultaneously holding back his own rising orgasm as he ran his penis over her silky breasts.
After what felt like an age that vampiress finally stiffened almost imperceptibly and he realised that she had orgasmed. Letting himself go he sent spurt after spurt of cum into Arcueids face. Without a doubt Arcueids face covered in white was one of the hottest things he had ever seen.
Then suddenly he was assaulted by a mix of pain and pleasure. He had taken a break for a moment too long and he felt himself violated by one of his friend's dainty fingers, even worse than that the lucky amateur had somehow managed to hit his prostate on her first try. He looked at her again and saw her white splattered face turn into a triumphant grin. Then the world dissolved into a single point and his brain overheated.
xxx
Shirou lay face down with his rear in the air. For the last fifteen minutes Arcueid had held the upper hand and she had known it. She had found a cheat to obtain victory and she had pressed that button relentlessly. While the recent past had blurred together Shirou knew he must have orgasmed ten times. Without a doubt this was one of the greatest benefits and downsides of having his fluids replaced instantly. For him the refractory period didn't exist and thus he had been plunged into this hell of pleasure.
Finally it stopped and he found himself lifted up by Arcueid. "Did I win Shirou," the glorious stupid fucking vampire said.
"Yes," Shirou said. "You won Arcueid. "I'll give you your reward now. Just go on all fours and face that direction." The vampire gullibly did as he commanded and for just a moment he admired her.
Arcueid despite being a force of nature and the closest thing to a human shaped hurricane had always had a beautiful slender, svelte look. He unashamedly admitted to himself that the bare ass of the vampire as well as her eagerly dripping slit would be a sight he would remember for his whole life.
That mental picture saved away it was time for his revenge. Placing his hands on her butt and massaging it he got a low rumble of appreciation for the vampire. Normally it was impossible to affect the vampire with his magic as her unquantifiably immense level of mystery prevented it. However he was not doing actual harm to her, her defences were lowered and he was sufficiently fucking motivated.
With not a word he turned up the sensitivity on her ass way up and brutally sodomised the unsuspecting vampire. Bringing his hands around his chest he once again grasped her nipples while jackhammering back and forth in an intensity that would severely hurt most human women but only served to further pleasure Arcueid. Her moans rose in pitch until she climaxed but Shirou didn't slow down after ten minutes she managed to turn the tables on him and they engaged in some hard vanilla sex.
xxx
Then Arcueid pinned Shirou and attempted to suck out all the water in his body through his penis for minutes on end.
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Then Shirou stimulated Arcuied's clit while both her vagina and ass were filled with rushing vibrating and expanding and contracting water until the water he had used was dwarfed by the water Arcueid produced.
xxx
Then Arcueid again tried for the blowjob but Shirou turned it into a sixty-nine and they indulged in mutual pleasure for half-an-hour.
xxx
Then Arcueid got the upper hand and repeated her initial win by rimming Shirou's prostate. However this time she held him upside down while doing it with his shoulders on the floor and masturbated him almost causing him to be covered by his own cum.
xxx
Shirou topped this by freezing Arcueid in an iceblock leaving specific parts exposed to the air which he then proceeded to vigorously fuck.
xxx
The trend continued throughout the night with one gaining the advantage before another took it back. The level to which they took this competition of theirs would have killed anybody without their levels of endurance and regeneration. As it was after the eighth hour Shirou found himself growing more and more tired and by the ninth he had blacked out.
xxx
Shirou woke up to the glorious sight of Arcueid standing nude across the room from him. His memories came back to him and he looked around for his clothes. With a flash of annoyance he realised that they didn't seem to be there. Standing up he realised with a start that the room was clean.
Arcueid noticed him stand up and came bouncing over to him. Before she could say anything he stopped her and asked the question on his mind.
"Arc who cleaned the room?"
"Nine did," she said smiling. "I didn't know he could enter when it was locked but he came down at four and tidied it all up."
Shirou didn't know that either. Still he breathed a sigh of relief. Nine was both dependable and discreet the perfect butler.
"He also said that breakfast was ready when we want it," Arcueid said innocently.
"Fucking Nine," Shirou thought in his head.
"Shirou," Arcueid said seriously to him and he immediately focused on her. "What does this make us?"
Hundreds of answers ran through his head but Shirou decided against lying to his friend. "We're friends with benefits, sex-friends or fuckbuddies. Arc I can't promise…" He trailed off as his vampire friend put one of her slender fingers over his lips.
"Second question," she said. "Do you want to get back to it?"
"Hell yeah," he said.
And in that instant both pounced at each other.