Hey everyone here's a one shot I did for fun plus I like cat girls so what the hell, takes place after Kyousuke discovers Kirino's secret.

Warning: Slight Lemon

Disclaimer: I don't own Oreimo

Te: "Alright class turn to page 232 in your history textbooks, today we'll be learning about one of the most anomalous members of our modern society the homo felinus or as most of you would refer to as the cat people or as probably none of you refer to as Khajiit, a few million years ago during the stone age arose a new intelligent race known as homo felinus, as their name suggests they were a species of upright walking cat like apes, their presence is seen as odd by archeologists since there are no signs of their existence going past three million BC and thus no ancestral species to link them to Earth's evolutionary tree leading some to theorize that they originated either from space, another dimension or haha the hollow Earth since the earliest known fossils of homo felinus were discovered in several areas within the arctic circle, structural analysis of their bones suggest that early homo felinus were actually much more cat like than their modern day counterparts, turn the page, as you can see from the picture shown homo felinus sported many physical features that their descendants don't such as a mussel, much larger fangs, retractable claws, a hairy body, and various amounts of nipples."

Da: "Hot damn these guys were ugly!"

Ha: "Shut the hell up Daichi!"

Te: "Calm down you two, now it was shortly after their appearance that a certain event occurred that would lead to their virtual extinction and that was…breeding season, it was at this time that the females of the species would obviously go into heat and produce pheromones to coerce the males into breeding though due to their odd physiology these pheromones had a similar but more extreme effect on male homo sapiens that can still be seen today. It was so extreme in fact that it would cause them to literally lose their minds in a sexual frenzy and individuals would even go so far as to kill large groups of male cat people just to get at one female and depending on how long the heat lasted many would die from either dehydration, exhaustion, or starvation. Also given that cat people are extremely monogamous the females would then be permanently bonded to their male captor, if they didn't die afterwards, which I'm sure would be a surprise to them after coming down from their frenzy, the female's pheromones would even alter so as to only effect their new mate when their next heat came."

Da: "Wait were the humans able to get the cat women pregnant?"

Te: "Well Daichi if you simply take a look at some of your class mates the answer should be obvious."

?: "Dumbass!"

Class: "Hahahaha!"

Te: "It was repeated cycles of this over the next 2 million years that would cause the homo felinus to essentially go extinct even the hybrids would fade into near nonexistence since the males would always be outcompeted for breeding rights with hybrid females and were seen as unattractive by human females to be able to breed at all and thus the genus was diminished to nothing but a one in a hundred thousand hereditary mutation where only the ears and tail are prevalent, that is until four hundred years ago when a group led by Martin C. Lawd began the movement to establish the cat people as an official race by calling people with the mutation from all over to only marry other cat people and encouraging normal people to set up these unions."

Ko: "So him and his group pretty much acted as an old timey version of cat people meet . com?"

Te: "Uh yes, anyway it was because of his efforts that the cat person population grew to what it is today even gaining influence in societal structures of many countries and becoming a large part of Japanese pop culture especially in the anime and manga industry."

As the teacher went into further detail about the history of cat people I began to zone out, I wasn't really in the mood to listen to all this given that I don't have good relations with the cat person I'm currently associated with.

Te: "So since most cat girls go into heat at such a young age some air spray companies like Fedravt decided to make new lines of sprays to neutralize their pheromones while at the same time freshening your home."

{Biiiiiingboooong}

When class finally ended I headed home with Manami as usual until we parted ways, upon entering my house I gave my greeting and walked into the living room to see my sister Kirino, a cat person, laying on the couch talking on the phone while her tail mindlessly waved in the air.

Ki: "Blah blah blah clothes blah blah blah shoes blah blah blah stupid blah blah blah brother blah blah blah oh no he didn't."

Jeez not even a "welcome home" I thought we at least made some progress.

I decided to see if I could get her attention or at least get her to acknowledge my existence.

Ky: "Hey!"

She momentarily turned her head towards me as if she heard something that wasn't really there then immediately went back to talking on her phone.

Ky: "Ch."

Brushing that aside I continued to the fridge to receive my daily helping of barley tea and I wanted to hurry since the carton was almost empty but when I opened the fridge I noticed a new unopened carton of barley tea sitting next to the old one, crediting it to mom being generous I took the old carton and drank down what was left inside before throwing it into the garbage, having done that I headed to my room to relax until dinner, a couple of hours later mom called me down earlier than usual.

Yo: "Kyousuke?!"

I got up and made my way down to the living room to see my parents with some overnight bags.

Ky: "Hey guys what's going on?"

Dai: "Kyousuke didn't Kirino tell you? Your mother and I are leaving to meet with some relatives for the weekend."

Yo: "She probably forgot, anyway Kirino is upstairs and I stocked the fridge with plenty of food so you should be fine until we get back now be sure to try and get along with your sister for once or at least try to tolerate each other alright Kyousuke?"

Dai: "And be sure to watch for any skulkers I've already caught a few spying on Kirino it's only a matter of time before they try something."

Ky: "Sure thing dad."

After seeing them off at the door I decided to spend the next few hours watching TV, luckily with no interruption from Kirino, until I got hungry and got some cup noodles to heat up in the microwave, while I was standing in the kitchen waiting for my food to finish I heard the living room door open, knowing it was Kirino I decided to just kept my gaze fixed to the microwave until I suddenly felt a pair of arms wrap around my stomach.

Ky: "Gah!"

Surprised by this I jumped away and turned around to see that my assailant was Kirino.

Ky: "K-Kirino?"

Ki: "Kyousuke."

It was then that I noticed Kirino's odd appearance, she was waring a red negligee and she had a dreamy almost drunk look on her face and I began to notice an odd smell about her as she began to walk closer to me.

W-wait is she in her first heat?! Crap this bad.

Ki: "Kyousuke."

Before she could get any closer and her scent could have it's effect on me I pinched my nose and ran past her to my room and sat against my door to block it.

Jeez the night mom and dad leave for something had to be the very night Kirino goes into her first heat and where the hell did she get that lingerie from?

As I was thinking this Kirino began to rub herself against my door beckoning me to come out.

Ki: "Kyousukeeeee I need youuuu, please come out."

Ky: "Kirino you're not in your right mind try to get a hold of yourself I'm your brother."

Ki: "Kyousukeeee, I need my big brothers thick, hot-

Ky: "KIRINO are you hearing yourself right now?! Do you really want to do something like that with your own brother that you hate?"

Ki: "I don't hate you just open the door and I'll show much I really like you."

After ten minutes of this things finally went quiet and I heard her walk to her room.

Ky: "Finally she's gone, wait a sec I completely forgot to lockdown the house."

Shortly after Kirino was born dad had deployable steel shutters installed on all the house's entrances in preparation for this and there are two activation switches both of them next to the front door on the inside and the outside.

If I can make it outside and flip the switch I can call mom and dad and they'll be able to take care of this, wait why don't I just call them now?

I reached into my pocket for my phone only to find out that it wasn't there.

C-crap I left it in the living room! Okay forget about the phone just go downstairs and grab the anti-cat girl Fedravt spray from the bathroom and flip the outer lockdown switch without her hearing you, sounds easy enough right? Plus if I don't lockdown the house who knows what'll happen if Kirino gets outside, dad already caught a few guys snooping on her and they all had ties with human trafficking in the black market, all one of them would have to do is have their way with Kirino while she's in heat and she'd do whatever they want, well there's no way I'm going to let that happen she may be a bitch but she's my sister.

After psyching myself up I cracked open the door and peered down the hallway, seeing that it was all clear I silently moved downstairs and quickly made my way into the bathroom to grab the Fedravt spray. I snuck out of the bathroom and tiptoed toward the front door but just as I was about to grab the handle I heard the living room door creak open, paralyzed with fear I turned to see Kirino standing there, still dressed in her red negligee and her tail slowly waving around.

Ki: "Hey there big brother going somewhere?"

Ky: "G-g-g-ge-m-muh."

She then held up her smart phone which was opened to an app that displayed an unlocked padlock picture on it and with a wave of her thumb she pressed on it and the entire house rung with the loud sound of all the steel shutters closing at once and I knew my time was up.

{SLAM}

Ky: "Th-there's an app for that?"

Ki: "Why are trying to run from me big brother? All I want to do is make you feel good."

Acting quickly I pulled out the Fedravt spray and aimed it at her but before I could pull the lever she dashed towards me and slapped the bottle out of my hand and heel kicked it into the living room. Knowing she had the upper hand she pressed herself against me holding me to the wall.

Ki: "There's no use resisting big brother I've set the lockdown to last for the next two days and my phone is password protected so you might as well just give in."

I stood there against the wall holding my breath slowly losing all hope of escape.

I can't believe this, I can't believe I'm actually about to do THAT with my own sister and I might actually die from it too, what can I do?!

Thinking it couldn't get any worse than this I made a last ditch effort to run to the living room for the spray but given that I had already held my breath for almost a minute my muscles were weakened and Kirino was easily able to trip me, I laid there flat on my face and my breath released taking in the pungent aroma of Kirino's scent she then moved to sit on top of me talking into my ear.

Ki: "Just give in big brother we have the next two days to have all the fun we want."

I began genuinely cry as I attempted to drag myself to the living room but I grew dizzy from the powerful smell and everything started to get fuzzy.

Ky: "Please Kami no."

After that everything became a blur, I was only able to make out a few scenes of Kirino bouncing on top of me, some of her bum moving back and forth as I pierced her from behind with my hand holding tightly to her tail, and then holding her close as I climaxed inside of her in the missionary position all while she screamed "I love you" over and over again…I woke up to the sound of metal clacking and I opened my eyes to see the steel shutter of one of the windows rising back into place. I looked around to see that I was in Kirino's room and I was sitting naked in her slightly damp bed though Kirino was nowhere to be seen.

What the hell just happened? Has it already been two days?! {grooooowl} I sure as hell feel like I haven't eaten in two days.

I moved to get out of bed but when I tried to stand up I momentarily became very dizzy and almost fell over but I was able to keep myself stable, a strong stench filled the room which to my surprise caused me to become aroused.

Dammit why did this have to happen?

I was suddenly overcome with a feeling of nausea and I ran to the bathroom downstairs to empty my stomach and after ten minutes of nothing but dry heaving I took a shower to clean myself of this stink. After I finished I went back upstairs to get dressed and back downstairs to get something to eat, when I opened the living room door I saw Kirino standing in front of the stove cooking something.

Ky: "Geh?!"

Ki: "Oh hey Kyousuke, come and sit down I made you breakfast I'm sure your starving after that marathon we did."

Well she's definitely not back to normal but she doesn't seem as crazy as before and I'm not losing my mind right now so she not producing her pheromones anymore, maybe her heats actually over.

Ky: "Okay."

I did as she said and sat down at the table wondering how I'd live with myself after what I just did and how I would tell this to our parents.

Ki: "Here."

Ky: "Uh thanks."

I looked down at my plate to see two partially cooked eggs with pieces of the shell in them, a sausage cut in half that was still red in the middle, a slab of raw salmon, and two pieces of buttered toast while on her plate sat nothing but a bran muffin and some tuna with crackers.

Ki: "I hope you like it {kiss}."

Ky: "Uh."

Did she actually just kiss my cheek, who the hell is this girl?!

Ky: "Kirino what day is it?"

Ki: "It's Monday, I decided to let you skip school since you looked really exhausted and mom and dad should be back home tonight."

Ky: "Okay then."

I poked at the food and nibbled on my toast while Kirino stared at me from the other side of the table after a while she pushed her plate over next to mine and got up to sit beside me and lean her head on my shoulder, I could feel the vibration of her content purring.

Wait does she think we're actually in love?

Ki: "So Kyousuke what do you think of the food?"

Seriously going from a bitchy ice queen to a sweet lovey dovey princess is really disturbing especially knowing it's because of what I did but what's done is done so I have to do what I can to get things back to normal, starting with this.

Ky: "The food's terrible, the eggs are undercooked and full of shell pieces, the sausage is still raw, and I don't like raw salmon."

Ki: "Well that's expected."

Ky: "Eh?"

Ki: "It is my first time really cooking a meal and now I know I still have some things to improve on so thanks for giving your honest opinion, hm most men would've lied to keep from hurting my feelings I'm glad to know you're not one of them."

Ky: "Dammit."

Ki: "It's okay if you don't want that stuff but at least eat your toast, you need to have something in your stomach if we're going to get back at it."

Ky: "Back at it?!"

Ki: "Yeah we are trying to have a baby."

Ky: "What?!"

Ki: "You were talking about it the entire time we were doing it, you kept saying "I'm going to fuck a baby into you" and the amount of spunk you let out was enough make an army, hmhm you really know how to get a girl going big brother."

Ky: "Alright Kirino that's enough! Don't you find anything wrong with this?! I'm your brother we shouldn't be doing any of this!"

Ki: "…Listen Kyousuke you might as well get used to this."

Ky: "Huh?"

Ki: "What me and every other cat person has is a psychological disorder that prevents us from being attracted any person other than the one we lost our virginity to and there's no way of fixing it so any attempt at trying to separate me from you would only damage me further and probably cause me to go into depression, would you really like to be the cause of that?"

Ky: "B-but don't you feel sickened by this?! I'm your brother the brother which you hate how can you sit there calmly knowing what we did?"

Ki: "{sigh} You really are dense you know that, if I really did hate you don't you think I would have been more expressive about it, to be more accurate I was frustrated with you."

Ky: "Frustrated?"

Ki: "I put out so many signs, I even keep the fridge stocked with your favorite drink."

Ky: "Wait you're the one that's always buying the barley tea?"

Ki: "Who else do you think buys it? It's not like mom or dad do anything nice for you."

Ky: "…"

Ki: "Seriously it pisses me off sometimes when I see how they treat you and it's all because of that glasses bitch."

Ky: "What does Manami have to do with this?"

Ki: "Nothing forget it anyway I thought since we're taking the day off we could play some games since you're most likely not in the mood for more fun in the sack."

Ky: "Guh."

Ki: "Hmhm you'll learn to love it, plus you could use the time to figure out what you're going to say to our parents I mean they are going to find out anyway when you go crazy in my next heat."

Ky: "That's right when dad finds out about this he's going to falcon punch me right into my grave."

Ki: "I'm sure you'll figure something out besides it's not like it was your fault you were simply put under the powerful spell of my cat-womanly charms what you did was outside of your control well except for everything that you said."

Ky: "What?"

Ki: "My pheromones may have forced your hand but it only loosened your lips, everything you said in your frenzy was straight from the heart."

Ky: "…"

Ki: "I guess deep down you really do want to fuck a baby into me."

Ky: "Whaa-aha-ahaaaa why did this have to happen to me?"

Ki: "Stop your blubbering, come on I just bought a new little sister game in know will cheer you up maybe enough to get you in the mood for some role playing."

Ky: "Yeah sure that sounds good."

Ki: "Good."

Kirino took my hand and dragged me up to her room to play games as I wondered what would my future with her hold? Would I live to see tomorrow? Should I get used to the fact that we were going to have kittens? I don't know but as Kirino said you'll learn to love it.

AN: Hey everyone hope you enjoyed this little AU one shot I did a little pandering I know but who doesn't love cat girls, I'm actually more surprised that no one has thought to make a cat girl Kirino fic at all but here's to hoping someone tops mine with a better one.