Little Sister, Don't Use Me as Your Fap Material! ~Operation to Capture the Perverted Brother-Sister's Special Fetish Girl~

Chapter 5: Brother and Sister, Two Wings of One Body

“Madoka… What the hell are you doing…?”

On my bed, in my room, a shameless slut was burying her face in my used tissues while frantically playing with her pussy.

That was unmistakably my little sister, Aoyama Madoka.

“……”

After a brief moment of silence…

“Hehe~ So Onii-chan finally caught me~”

Her reply was much calmer than I expected.

Her bold attitude actually left me slightly taken aback.

“You say ‘caught you’… what exactly were you doing?”

“You already know exactly what I was doing, yet you still bombard a girl with questions? Onii-chan, you’re surprisingly sadistic~”

With a flushed face, she grinned and brushed her glossy hair back.

“I was in the middle of ‘having fun’ while using Onii-chan as my fap material♡”

……Huh?

Using Onii-chan as fap material?

What the hell is this girl saying?

“You’ve got the same face as a pigeon that just ate a machine gun, but Onii-chan jerks off to me too, right? It’s exactly the same thing.”

“No, but that’s…”

I couldn’t bring myself to say “that’s because I like you.”

Telling her that now felt like there would be no turning back, so I could only stand there silently.

Using the bounce of the bed springs, she lightly hopped to her feet.

Still completely naked, she slowly walked toward me.

Just like she did on the way to school this morning, she looked up at me with those big, upward-gazing eyes, staring straight into my face.

At the same time, her right hand reached toward me, and her wet middle finger slowly traced across my lips.

My slightly dry lips were given a glistening coat of moisture.

Gulp. I unconsciously swallowed hard.

Sensing my tension, she grinned again like a little devil — or rather, like a rookie succubus.

“Hey Onii-chan, can I say one thing first?”

“W-What…?”

D-Don’t tell me… is she about to confess her love!?

I’m not mentally prepared yet…

“Don’t interrupt a girl when she’s about to cum, you stupid brother!!!”

……Um, does this mean I’m currently being scolded by my little sister who was freely masturbating on my bed?

Moreover, the historic first time she calls me “Aniki” (big bro) is being wasted on such a shitty line… As her older brother, that’s honestly too sad.

“You really have zero delicacy, Onii-chan. It’s always been a problem.”

I won’t deny that I lack delicacy, but I also don’t want to hear it from you.

“By the way, if I did have delicacy, what would’ve been the correct action?”

“First of all, you should knock before entering a room!”

……This is my room, though.

“I know what you want to say…”

Yeah, obviously I get it. There’s no need for me to knock before entering my own room.

“You wanted to say ‘Hell yeah! The only thing I knock is a girl’s cervix!’ right?”

……No, that’s completely wrong.

Also, the image you have of me inside your head is way too dangerous.

“I do like that ‘manly’ side of you though~”

Don’t blush! I am definitely not that kind of guy!

Doesn’t she have a completely warped understanding of what “manliness” means?

If she’s expecting some loud, brash ‘teyandei’ type of character, that’s a pretty heavy burden for me…

“No, Madoka. Sorry, but that’s not what I wanted to say at all…”

“…Wait, was it ‘beranmei’ instead of ‘teyandei’?”

“Is there any meaningful difference between those two?”

“…Anyway, if you were moaning that loudly, there’s no way you would’ve heard a knock anyway.”

Is this level of logic too lacking in delicacy…?

……

“…You’re right!”

What should I do? My little sister is incredibly stupid.

“Well, Onii-chan does have a point~”

“I’d say I have at least a hundred points.”

“I at least wanted you to talk to me after I finished cumming properly~”

“Even if you say that… it’s hard to tell when a girl is ‘finished’…”

“I’ve told you before that I always squirt when I cum!”

“No, that’s the first time I’m hearing this…”

“Onii-chan, you look like you just got hit with shocking news.”

“From my perspective, it feels more like ‘a worm in my ear’.”

“‘Aoyama Madoka squirts when she cums’ — This will be on the next test, so make sure you memorize it!”

I have zero intention of taking such a stupid subject.

“Madoka-san, why are you so ridiculously worked up?”

“Because someone interrupted my masturbation right at the climax.”

“Is that how it works…?”

“Onii-chan, just imagine it. You’re jerking off to me, right on the edge of cumming, and then Mom calls out ‘Kazuya~ Dinner’s ready~’. How would you feel?”

“I’d think ‘Shut the hell up! I’m at the good part, so shut your mouth you shitty hag! I’ll kill you!’”

“That’s even more extreme than I imagined… Poor Mom.”

“But yeah, you’re right. Getting interrupted at that moment would make anyone extremely worked up…”

“See~?”

“…Sorry for interrupting you, Madoka.”

“Can’t be helped. I’ll forgive you this time.”

I’m not fully convinced, but if bowing my head settles things peacefully, then fine.

“Now that we’ve made peace, can you at least put something on? It’s really hard to know where to look…”

While staring directly at her pink nipples, I said that.

“So, why were you doing that on my bed?”

……

After a short pause.

“Onii-chan, do you know about ‘Dr. Sisconga’?”

Wearing my slightly oversized T-shirt, Madoka sat on the bed and suddenly asked me that question.

What the hell is that? Sounds like the name of a monster from a hunting game.

“No, I don’t.”

“Figures~ Well, Onii-chan isn’t very knowledgeable after all.”

Hey, I don’t mind, but please apologize to the readers.

No one knows who that is.

“Dr. Sisconga = Dr. Sikorsky. He’s the proposer of the Ani-Dick Cell and the superhuman ability theory caused by it.”

Wait… superhuman abilities?

“Onii-chan, the truth is… I’ve awakened superpowers!”

Honestly, I’m more interested in hearing an explanation about why you were masturbating to me earlier than hearing about superpowers.

“Well, I’ll explain everything in order, including that part.”

Is this going to connect properly? Can you actually link the superpower story to the part where you were using your brother as fap material? You sure you didn’t start talking without thinking it through?

Ignoring my anxiety, the self-proclaimed superpowered girl began to speak.

“Do you remember when I was bedridden for 10 days a year ago due to poor health?”

“Yeah, of course I remember. I was really worried about you back then.”

At the time, our parents told me they never figured out the cause.

“During those 10 days, I didn’t have a high fever, headache, or any normal symptoms like that.”

“Then what exactly happened during those 10 days?”

“For those 10 days — roughly 240 hours — I was continuously experiencing ‘sexual climax’.”

I’m not going to say “Oh, I see!” to that.

What kind of B-grade indie eroge plot is this?

“After that 10-day ‘continuous orgasm,’ for reasons I don’t fully understand, three ‘powers’ awakened inside me.”

“Haha, what? Can you bend spoons now lol?”

“I can’t bend spoons. But I might be able to bend Onii-chan’s dick lol.”

I quickly stepped back twice to avoid her left hand approaching my crotch.

What a dangerous girl.

If you have time to bend things, how about helping me soften this hard thing instead?

With an expression that seemed to say ‘Tch, how boring~’, she continued explaining the three abilities she had gained.

Since it was quite a long explanation, I’ve summarized it for the readers.

Gentlemen who are only interested in the erotic parts may freely skip this section.

See you in the next episode.

【Dr. Sisconga’s Ani-Dick Superpower Theory】

- The manifestation of Ani-Dick Cells causes the host to experience nearly 10 days of continuous “sexual climax.”

- Upon the end of this climax, the Ani-Dick Cells activate within the body. The abnormal “electrical signals” cause symptoms that can only be described as “superpowers.” This has been confirmed in multiple past cases.

- There are a total of 10 types of so-called “superpowers” confirmed in past cases. Madoka possesses 3 of them.

- In order to stop the activation of Ani-Dick Cells, it is necessary to introduce “Aninael Antibodies” into the body.

- Aninael Antibodies have been confirmed to exist only in the bodily fluids released during climax by girls under 22 years old who possess “abnormal sexual fetishes,” commonly known as “Spell Masters” or “Masters of Sexual Power.”

- The bodily fluid must be collected within 30 minutes of being released outside the body, and the antibodies must be obtained from it.

- It is believed that the superpowers gained from Ani-Dick Cell activation serve as a means to help obtain these Aninael Antibodies.

【The 3 Superpowers Awakened in Aoyama Madoka】

① Sexual Power Detection (Karma Scale)

- Allows her to visually determine whether a person is a “Spell Master.”

② Sexual Fetish Exposure (Melt Down)

- By correctly “understanding” a Spell Master’s abnormal fetish, she can learn the exact “climax conditions” required for them to release Aninael Antibodies. However, it only activates when she directly witnesses the Spell Master in the act.

③ Pleasure Ascension (Paradise Market)