Ever since reading the sex scenes in Heaven's Feel route after watching Fight Club, there's been an idea that's stuck with me. This is what that idea lead me to. I'd dedicate this to Mike1984, but his ass is grass.
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“Oh sempai, I haven't been fucked like that since grade school.”
That, along with “happy birthday grandma”, “I have HIV,” and anything involving mollusks, is not a phrase one wants to hear in post-coital bliss. And it is here we find Shirou Emiya, filled with equal parts regret and confusion.
“Run that by me again, Sakura.”
Sakura dove under the covers with a meep, apparently thinking if her sempai couldn't see her, maybe he'd forget she was there. He could be kind of dense at times. It did take an act of near sexual assault on her part just to get to the glorious moment where she warmed her sempai's bed. A moment she just ruined.
Shirou, undeterred by the makeshift blanket shield, pulled the covers off his partner. “Seriously, did you say grade school?”
“It's a long and uncomfortable story, sempai, so can we please drop it?” Sakura mumbled into her chest.
Shirou held her close, partially to comfort her and partially to keep her from running away. “Sakura, you promised there'd be no secrets between us.”
“But I like my secrets,” she moaned. He gave her a stern, paternal look; something she wasn't used to getting with such tenderness.
“Sakura...”
“Alright fine,” she threw her hands up, “I'll tell you. Due to...various circumstances, I need semen to live.”
“You what now?”
“If you're going to ask questions through the whole thing this is going to take a long time sempai, so please save them until the end.” Sakura took Shirou's bewildered look as a cue to keep going. “I'm sure sis-Tohsaka-sempai has told you this already, but blood and semen are rich in mana. Given the method of my indoctrination into the Matou clan, I require a large amount of mana regularly. My brother provides it in the form of semen, which I take in to me via tantric ritual.”
“So Shinji's been having sex with you since you were kids.”
Sakura blushed. “In so many words, yes. At grandfather's insistence, Brother would give me his semen.”
Shirou ran a hand through his hair; the post-coital glow all but snuffed out. “Your granddad made you and Shinji have sex. That is profoundly fucked up.”
“It was either that or drink his blood,” Sakura said defensively.
“But wait, if you need semen, how did you get your mana before he hit puberty?”
“Like I said,” she said harshly, “it was either blood or semen.”
Shirou paled at this. “Couldn't you have just kept drinking his blood? I mean, that's weird, but at least it's not incest.”
“I am not a vampire, sempai, regardless of what Realta Nua implies.” Sakura said, proud of this fact.
“But that means you'd rather fuck your brother,”
“Adopted brother.”
“...Adopted brother than not fuck him.”
“Would you believe I have a very good reason for that?” Sakura blushed again. “Brother, I mean Shinji, is amazing in bed. He's useless at pretty much everything else, but he's a tiger in the sack.”
“That just explained things I never wanted to be explained,” Shirou said. He now knew why girls seemed to fall for Shinji''s weedy charms. What he wanted to know, was how to crawl out of this conversation without upsetting Sakura. He longed to go into the shed and think about projecting swords or being a superhero or anything other than his former friend's sexual escapades with the sister he just had sex with.
“Don't worry sempai, you're amazing too,” Sakura said, trying to play to his ego, “So strong and forceful, but so tender at the same time.” She gave her lover a sly smile, “And if I can be blunt, you're hung like a horse.”
Shrou couldn't help but blush and smile at that. “Really? I mean, I haven't had a lot to compare it to and- wait a minute why are you telling me this?”
Sakura ran her hand up and down Shirou's inner thigh, “Because it's true. You really are better at this than he is. It's become a job to Shinji. He hits and quits. But with you, it's truly making love. You're like a harlequin romance protagonist come to take me away; my superhero during the day and my marathon man at night.”
“I'm glad I can be your superhero, but I don't know about the other thing.” Pride and disgust were waging a brutal war inside of Shirou.
“Well you are definitely my marathon man, sempai,” Sakura nuzzled his chest, “you just keep going and going and going.”
“And does Shinji do that too?” Shirou asked. Now that the floodgates had been opened, curiosity was getting the better of him. Shinji bragged about his conquests, but he never really went into detail. Up until now, Shirou was starting to believe Shinji was making some of them up.
“Don't worry, you last longer than he does,” Sakura giggled, “Brother's got a lot of technique, but he's a bit of a quick shot, if you catch my drift.”
Shirou shifted uncomfortably besides Sakura; she was tracing circles on his broad chest with a finger and he wasn't sure how to feel about that. On the one hand, beautiful woman who was very into him who seemed to want to go another round. On the other hand, beautiful woman discussing sexual partners in bed. And the partner was her brother and his (former) friend. Both his heads swam in confusion.
“If we're going to be talking about Shinji like this, could you please not call him brother? It just makes this whole thing more awkward and uncomfortable.”
“Sorry, force of habit,” she said. “But yeah, he's done like that,” she snapped her fingers, “and he just leaves me to clean up after myself now. When we were younger, he would really explore me and try to make me feel good. Now he has other girls for that.” There was a note of sadness in her voice.
“Are you actually disappointed that your brother,”
“Adopted brother.”
“Whatever doesn't have sex with you like he used to?”
Sakura turned crimson. “No, I mean, not really. It's just, it was a simpler time, you know? We were playing house and Shinji always made the best cream pies.”
“I think I'm going to be sick.” Shirou felt the weight of myriad curses in Sakura's glare, “that your granddad made you do this.”
Sakura put her hands on her hips, which let the covers bare her bountiful breasts. “Would you prefer it if I told you grandfather was the one who gave me my necessary mana intake?”
“Dear sweet god no,” Shirou yelled at Sakura's breasts despite himself. “It's just, why did your granddad have to do this in the first place?” He managed to say that to her face.
“Promise not to freak out?”
“It can't be weirder than having sex with your...adopted brother, can it?” Shirou was met with a crushingly awkward silence. “Please tell me it's not weirder than having sex with your adopted brother.”
“The Matou family crest is passed down via worms.”
“Oh.” Shirou said, deadpan. “Are these happiness worms?”
Sakura pulled the sheet back over her breasts. “Happiness worms aren't really a thing, sempai. If you're a female, they make you happy in a sense. But it's more they make you really, erm, aroused.”
“Am I going to get these worms now?”
Sakura laughed. “Of course not, sempai; if you had the worms they would've killed you by now.”
“That's comforting, I guess,” Shirou shuddered. “Are these magic worms?”
“They taught my body magic, so I would assume so.”
“Wait, what do you mean by 'taught your body magic'?” Another awkward silence.
“Well, grandfather would teach me magic by throwing me in a pit of the worms and they'd teach me magic.”
Shirou put a hand on Sakura's shoulder and gave her another stern look. “Okay, you know I'm not going to believe that's the whole story after everything else you've told me.”
“Why not,” Sakura said meekly.
“Because when someone says they learned something with their body, especially someone with as interesting a sexual history as you,” Shirou felt the pressure of curses again, “that means they had the lesson fucked into them. Sakura, did these worms rape you?”
Sakura pulled away from Shirou and into a ball. “They taught my body magic. That's all I'm going to say.”
“Dammit Sakura, I can't help you if I don't know what's going on with you.”
“You want to know what's going on with me? You really want to know?” Sakura gave a bitter chuckle. “I got fucked by dickworms since I was seven. I didn't learn what masturbation was until a few years ago since I was getting fucked constantly. I have to constantly crave cock because if I don't, the worms inside of me will eat me alive. There, does that make you feel better? Now that you know how filthy I am, am I still good enough for your hero complex?”
Shirou kissed her, stopping her self-abuse dead in its tracks. He pulled her close, so close their hearts beat as one. Sakura returned the kiss with passionate hunger, desperately hoarding the love and warmth the man she loved gave her.
“Does that answer your question?” Shirou said. Sakura gave him a downright predatory grin and pounced on him.
“No it doesn't,” she said, straddling him, “I'll just have to get the answer from your body.”
XXX
“Do I really have a hero complex?” Shirou asked, post-coital glow restored.
Sakura hit him with a pillow. The mood had already been ruined once before; she wasn't going to let it get ruined again.
“Oh come on, you can't just lay all that lewd stuff in my lap and then clam up when it comes to cleaner topics.”
“But sempai, I just want to bask in you for a little while,” Sakura said, head resting on Shirou's chest.
“Fine, go ahead and bask," Shirou said sharply, "I'll just take the hero thing as a compliment.”
“You're cute when you sulk, sempai,” Sakura yawned, “it makes you look intense.” With that, she fell asleep.
Drained and happy, Shirou quickly followed suit. He never did learn what Sakura meant when she said he had a hero complex. If she was going to teach him what she meant with her body, he didn't mind staying ignorant.