BY : Nuterino
Category: +. to F > Bible Black
Dragon prints: 1860
Disclaimer: I do not own Bible Black or its characters, it belongs to Active Software and Kitty Media. In addition, I will make no profit from this fic as it is for entertainment purposes only.

This book... it seems to be written in some sort of ancient language, definitely something I don’t understand. My only hope is my big sister Yukiko, considering her credentials in language and translating and all; it’s just a shame I have to deal with her bullshit all the time! Always teasing me with those scant outfits, flaunting her giant breasts, talking about her sex life in graphic detail, it’s sick! Perhaps what’s even more sick is that my cock was starting to grow at the thought of the stories she’s shared at the dinner table, it’s just me and her in the house since our parents are moved away for work... UGH! I just need to get this book translated...


I stuck the key and into the hole and twisted it sideways. 5pm. Yukiko should be home from college by now, I’m pretty sure she’s not working today.






Maybe she’s running late... either way I need to start studying ASAP. I climbed the stairs so I could retreat to the solace of my room, there I could try, and fail, to work out this ancient text myself.




A faint noise emitted from my sister’s room, is she sleeping? God I hope she is. Creeping as quietly as I could, I approached the door and prayed to God that she wasn’t doing... you know what. Bracing myself I gently nudged the door open and peaked through.


My sister was as nude as the day she was born, her tight, round ass high in the air as she rubbed her vulva with wanton delight.


“Oh, fuck...” she cried in ecstasy. “Yes!”


A shocked gasp escaped my mouth; I’m not sure why, I knew this would happen.


Yukiko’s eyes shot open and darted in my direction.


“Taki! Didn’t anyone teach you to knock?” She sounded more amused than anything.


“God, I’m sorry!” I yelled as I stared in pure embarrassment.


“What do you want anyway?” she questioned, now with a slightly more irritated tone.


“I-I was just wondering if you could help my translate this book I found, it’s in some sort of ancient language; you’re good at that kind of stuff.”


“Oh, sure!” she replied, still absentmindedly massaging her vagina. “Just let me finish up and I’ll help you out. Maybe you can help me out with this, little brother, and we can get started sooner...”


“For God’s sake!” I shouted in frustration as I shut the door. I could hear her cackling like a madwoman. I wish she wouldn’t joke about stuff like that. My sister’s a nympho through and through and that’s reflected in her sense of humour. Everyday, I have to deal with her parading around in her underwear and making lewd jokes at my expense. I know she’s just joking. Right? Yes, of course she is! Slut or not, she would never want to fuck her own flesh and blood, surely she just enjoys tormenting me. After all, a few days ago at the dinner table, she was telling me how she was gangbanged by the entire baseball team, I doubt she needs her homely little brother to satisfy her voracious needs.


The only girl I need was Rika Shiraki, the golden haired goddess, the most beautiful girl in school. God, the things I would do to her... I’m hoping that this book has some sort of love spell I can use. My dick was begging to escape my pants, do I risk it? If Yukiko caught me masturbating after I witnessed her own, I’d never hear the end of it. 




Speaking of Yukiko, it looks like she’s finished, better not risk it after all. Christ, has she no shame? Acting in such a perverted manner, showing off her luscious tits, her toned, mile long legs, her perfect apple shaped ass... DAMN IT!


I retreated to my room, sat at my desk, and just hoped to God that this boner will go away in time. Dead cats, Grandma’s funeral, Grandpa’s scrotum, there we go, it’s gone!


The door swung open behind me, Yukiko swaggered in wearing nothing but a minuscule halter top and daisy dukes, I could see her white g-string riding up her hips. Fantastic. We’re back at square one.


“So what is it you need?” she asked while sucking at the juices on her fingers. “An ancient text? Hm. I didn’t even know you could read.”


“Just shut up and get over here,” I replied. God, she knows how to push my buttons.


She sauntered over to get a gander at the book. “Huh, a religious tome... you haven’t joined a cult have you?”


“What? No!” I responded, perhaps a bit too defensively. “It was in the school library, I borrowed it because I thought it looked cool.”


“Because it looked cool...” she mocked. “Christ, you’re never gonna get laid.”


“Goddamnit, is that ALL you think about?”


“Only, like, 90% of the time. Trust me, there’s no feeling like having your holes stretched out by some stud.”


Here we go again...




“Slobbering over his hot, juicy cock and fondling his huge balls...”




“Once he’s done with my pussy, I’ll let him fill my asshole up with cum and let it leak out...”




“Such a prude,” she laughed...


“Don’t talk about stuff like that, it makes me really uncomfortable.”


“I guess you’re right,” she chuckled as she gave my shoulder a shake. “Sorry, little brother.”


“Let’s just start.” I said in an exasperated tone.”


I handed the book to her and she began to quickly devour it, page after page. Say what you will about Yukiko but she’s smart as hell, top in the class, though hopefully that doesn’t have anything to do with “extra credit” she does for the teachers.


“Latin, English, French... I think this is Gaelic, maybe? Or it could be Welsh. You sure picked a doozy, Taki.”


“Well, can you figure it out?”


A smug smirk appeared on her face, “Of course! Who do you think you’re talking to?”


The next two hours were pretty tedious, we made some progress but not much. Most of the spells were pretty stupid, like defense against pyromancy, though there was one that caught my sister’s eye.


“A spell that cause a young woman to dance naked?” Yukiko giggled. “That sounds like fun!”


“Hey! Try translating that one,” I suggested.


"You little pervert!" She punched me in the arm. "If you even think about trying to get a lap dance out of me...”


“Ow! Stop it!" I yelled. "Jeeze! It isn't even real. I just want to know what it says. Forget it."


“Now, now..." she said, smiling. "Since it's for my darling brother, I’ll be happy to translate it for you.”


That was the Yukiko I knew. I spent the next 20 minutes considering the ramifications of such a spell while she translated.


“Alright, I'm going to read it for you now," she said. "Keep your ears peeled, pervert-boy."


“Knock it off," I replied. "I only asked for that one because it sounded more interesting than purifying a goat or whatever."


“Ready? Let's see...First you have to write the first letter of the woman's name in your own blood on a piece of virgin parchment."




“Unused, kinda like you." She rolled her eyes. "Next, you wrap the parchment around a rock and place it on top of the manuscript for Holy Mass, and recite the Lord's Prayer. Take the rock and bury it beneath a door through which she must pass."


“Hmmm..." I scratched my head. Whoever invented that spell had never lived in Tokyo. Everything was covered in cement.


“And this woman will go mad," Yukiko continued. "When you witness her dancing naked in a depraved manner, you must look on her not with envy, but with pity...Oh! There's a warning at the end."


“What does it say?"


“Always remember, this is not a spell for those faint of heart," she read. "Hear that? It doesn't say keep out of reach of children. Lucky you!"


“Aw, shut up." I waved her teasing away.


“That spell sounds dumb anyway," Yukiko decided. "Whoever wrote it must have had some serious issues with his girlfriend."


Having said that, she gave me a long, meaningful stare. I tried to look innocent, but in reality I was already wondering who I should try that spell out on. I mean, it wasn't going to work. There's no such thing as real magic, it's an oxymoron, but a guy can dream. Can't he?


“You're not thinking of trying it, are you?" She knew me too well.


“No," I lied.


“Well, if you're so anxious to see someone dancing naked..." She grinned at me. "Why don't you just ask me to do it. You don't need some old dusty book for that!"


She stood up and cupped her heavy breasts in her hands, giggling and swaying side to side while giving me seductive eyes


“Come on,” she said in a low, husky voice. “Don’t you want your big sister to dance for you?”


“No," I said, somewhat unconvincingly as I turned my back towards her. "Stop it, okay? Just stop."


“There you go! Look!"


When I turned my head, her breasts were right in my face. She pinched them just behind her swollen nipples, jiggling her tits and rubbing them against my hot cheeks.


“There! How do you like that?" she teased me. "Does it feel good?"


“No...” I squeaked. My penis was getting as hard as steel.


She raised her eyebrow, “Oh? Then what’s this?” She suddenly grabbed a hold of my swollen prick. “This little guy says otherwise.”


I couldn’t believe this was happening! My mind was split 50/50, my moral side begging to put an end to this and my devious side relishing in the exposed, depraved truth.


“Yukiko, we’re family! We can’t do this!” I begged.


“Exactly,” she replied with a smile and half lidded eyes. “We’re family, and family help each other out.”


I closed my eyes and hoped that this was a long and perverted lucid dream. Those hopes were quickly dashed as I felt Yukiko’s hot breath on my ear.


“I’ve waited long enough, little brother. It’s about time you got the hint.”


Any resistance I put up was quickly evaporated. I grabbed her head and her lips met mine, our tongues rubbed together as we gave in to our sinful desires. 


I finally released my cock from it’s clothed prison and let it stand free. It was a crimson red and covered in pre-cum.


“Ooh,” Yukiko cooed. “You’ve got a nice pecker on you, little brother. Come on, take your clothes off. I want to see you every inch of you naked.”


I obeyed without question and stripped at lightning fast speed, my slim body was covered in sweat. My sister pulled her top off and freed her gigantic boobs, giggling as she gave them a shake. Her shorts were next, she bended over as she slid them down her gorgeous legs at a painfully slow speed, her shapely ass jiggled once released from the constraints of her thong.


She squatted down and stared in admiration at my erect penis, I swear she could see stars. She began stroking it as she looked up at me with a smirk.


“Damn! This is one of the biggest I’ve ever seen! You’re hung as hell, little brother.”


“Thank you, big sister...” I groaned back.


“Tell me, do you think about me often when you jack off?” she teased.


“I try not to,” I replied in shame. “I thought it was wrong.”


“Oh?” Yukiko replied. “Well, who do you think of then?” She suddenly stopped stroking.


“Big sister!” I cried indignantly.


“Come on... I just want to know.”


Even when we’re breaking the most sacred of taboos, she can’t stop teasing me.


“This girl at school,” I relented. “Shiraki. Her name is Shiraki.”


“And what makes this Shiraki so great that she gets my dear little brother all hot and bothered?” she interrogated.


I thought about every possible thing, while also briefly pondering about a threesome with her and Yukiko, “Flowing blond hair... big tits... a nice, round ass... popular... unobtainable...” This was torture, I need to cum!


“She sounds alright, I guess,” Yukiko said rather dismissively. “But who’s hotter?”


“You are...” I whispered in a barely audible voice.


She grinned lasciviously, “What was that? I couldn’t hear you.”


“You are,” I replied louder.


“Who do you want to fuck more? Shiraki or your big sister?”


“Big... sister...” I croaked out.


“Right answer.”


With that, she suddenly took all 9 inches of my rock solid cock into her mouth, all the way down to my balls. God, I was in ecstasy! She slobbered and sucked on my rod with intense vigour, much like a porn star. Eventually, she took her lips off of my cock and replaced them with her heaving breasts. Her soft flesh felt amazing as she pumped up and down.


“Yukiko!” I moaned. “I’m about to...”


Before I could even finish, she once again wrapped her lips around my cock, sucking the head while pleasuring the shaft with her breasts.


I let out a pleasure filled bellow as I filled my sister’s mouth with my seed, she swallowed all of it as I expected and sucked any remaining remnants out from my urethra.


“You taste good...” she said dreamily while licking her lips. “Oh!” her eyes widened, “you came so much but you’re still so hard!”


Her wonder dissipated as her cock hungry confidence returned. She suddenly grabbed my shoulders and threw on the bed.


“I’ve watched you jack off from time to time,” she grinned sadistically. “I know how much you can cum when you’re horny enough. It’s time for you to satisfy me.”


She straddled my hips and looked down at me like I was a puny bug.


“You have no clue how much I want your meaty cock to stretch out my slutty pussy. I hope you’re ready.”


She grabbed the shaft and slowly slid down onto my prick. Even though, I just came, I feel completely fresh.


Yukiko threw her head back and moaned erotically, “That’s the stuff. Alright, you little pervert, get ready for the best fuck of your life!”


She began rocking her hips back and forth, the feeling was indescribable, her wet walls enveloped me and refused to let go. I grabbed a hold of her tits while she rode me like a bull. The room was filled with our moans of incestuous debauchery. I felt my balls contracting, I was cumming again.


“Big sister, I have to pull out!”


“It’s okay, little brother, I can just abort it. Shoot your milk inside of me.”


My penis erupted once more and filled Yukiko’s well used cavern. It felt so good, like I had died and gone to Heaven. Yukiko rolled off of me and caught her breath, she turned and smiled at me, “Think you can handle one more?”


She was insatiable! There was no way I could, I’m completely spent!


“Big sister, I’m sorry but I just can’t go on, my cock’s all worn out.”


She flashed a wicked grin, “Don’t worry, little brother, I know how to get a guy hard again.”


“What do you mean by- FUCK!”


My question was cut short as Yukiko suddenly lifted my legs and began rimming my asshole, she ate it like she was starving, I knew she was a slut but I didn’t know she did stuff like this!


Using her free hand, she began gently stroking my rapidly hardening penis. Fuck! It’s so wrong but it feels so good!


Yukiko eventually ceased eating my ass out, “Alright, little brother.” she suddenly rolled off the bed onto the floor on all fours, head down, ass up. “All that’s left... is this...”


I gazed in amazement as I witnessed her spread her fleshy ass cheeks apart to reveal the hole in the centre.


“Little brother...” she sang. “Fuck. My. Ass!”


I swallowed the nervousness in the back of my throat and approached, staring at this once in a lifetime opportunity. I pushed Yukiko’s back down a little so her face was on the floor, her ass even higher, it was like the forbidden fruit, defying the will of God for my own selfish pleasure.


With my cock in hand, I squatted over my sister’s posterior with my legs spread far apart. My almost silent conscience begged me not to go through with this but I ignored it; I was going to Hell anyway so why stop here?


I spat on Yukiko’s puckered asshole and finally made the trek into forbidden territory, the head of my swollen red penis slowly sank into the depths of her cavern of carnal lust.


“Big sister...,” I croaked out. The feeling was indescribable, It felt like her rectal walls were constricting my penis like a boa. 


The rest of my cock entered Yukiko’s asshole. This was it.


“Ooh~,” Yukiko moaned. “That’s it. Right there!” Her blushed face was twisted in animalistic lust.


I began pounding away at her tight asshole, it pleasured me in ways I thought were impossible. Leaning forwards, I wrapped my hands around my sister’s slim waist as I began fucking her harder. I could feel her gargantuan breasts brush my knuckles with each thrust.


Yukiko cried out in ecstasy, “YES! IT FEELS SO GOOD, LITTLE BROTHER! DON’T STOP!”


Our sweat covered bodies clashed together in this sexual fusion of immorality and debauchery, God could go fuck himself for all I could care.


I could feel the sperm in balls begging for release as I drilled Yukiko’s ass harder and harder, I couldn’t take it anymore.


“Big sister!”, I announced. “I’m about to...!”


“Do it!”, she replied. “Fill me up like the whore I am!”


I smacked my hips against her ass as fast as I could, carnal desire overtaking whatever rational thought I had. Yukiko’s moans and expletives completely dominated my hearing as my hot cock was on the verge of exploding.






Cum erupted from my penis and flooded my sister’s cavern, the warmth of her asshole and my semen sent shockwaves of euphoria and ecstasy throughout my body. Similarly, pussy juices squirted out of Yukiko’s vagina and onto the defiled carpet as orgasm overtook her. 


We had turned our backs on our family, society, and God himself by committing this unspeakable act of sin and I felt damn good doing it.


Slowly, I retracted my worn-out dick through Yukiko’s ass and collapsed on my back to the ground. Yukiko remained on all fours and sank to the ground, cum slowly leaking out of her asshole. We both panted in exhaustion following our act of depravity, attempting to catch our breath and make sense of what we just did.


Yukiko glanced over at me, “Not bad, little brother. Not bad at all.” A cheeky smile formed against her lips. 


She rose to her feet and stretched her aching body, as if this was just a regular work out. I stared at her stretched out holes as she bent over to pick up her clothes. To think this all started over an ancient book I found in the school basement.


Yukiko’s expression turned to one of deviousness as she sauntered over to my immobile body. She placed a foot on my chest as she leaned over to me, her 5’8” frame seemed gargantuan from where I was looking.


“Trust me, Taki,” she whispered. “We’re going to be doing this a lot more often.”


I could only mumble out pitifully, “Okay...”


She stepped off of my chest and started to walk away, “Good! I’m going to bed. I’ll help you out with that book tomorrow, ‘K?” She said as if nothing happened.


“Sure,” I replied. “Good night, Yukiko. I love you.”


“I love you too, little brother.”


With that innocent little exchange she closed the door.


I stared up at the ceiling as I tried to truly grasp what just transpired in the past hour. I couldn’t tell if having Yukiko as a sister was a blessing or a curse.


Definitely a blessing.


Using the last of my strength, I turned off the lights and crawled into bed. If this book resulted in this, who knows what I could do with it? I think I’ll use it on Shiraki tomorrow and bring her home to meet my dear big sister. What fun that will be.


My eyes closed on their own as I dreamt off all the possibilities that book had to offer. Saeki, Takashiro, even Imari... all of them will be tempted and converted by my book, the Bible Black.








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