Chemistry Set
by Sterling
Copyright© 2010 by Sterling
Erotica Sex Story: Evan Graham has an embarrassing secret. When his sister Alexa spreads it around the school, he gets furious -- and so does his father. For his living, the father makes medicines related to women's bodies. He looks the other way while his son uses his chemistry set to torment his sister. She soon understands that she truly deserves all he does to her. He extends his chemical reach to other girls who had spread his secret, and follows torment by fulfilling his sexual dreams.
Caution: This Erotica Sex Story contains strong sexual content, including mt/ft Ma/ft Consensual NonConsensual Reluctant Coercion Heterosexual Incest Brother Sister Spanking Humiliation First Prostitution .
I'm a senior in high school, and before I go off to college I wanted to write about my life so far. It's not your typical high schooler's life.
It all started when I was 14 years old, just starting my sophomore year in high school. I had gone through puberty. I had gotten pubic hair, my balls were bigger, I was horny as hell, and when I jerked off I spurted. But then there were the parts where I didn't quite make it into a hunky guy. I got a little taller and stronger, but not much. I didn't have any facial hair, and my voice had changed a little bit -- enough to turn me from a soprano into an alto. I'm 5'4". All in all, I was great fodder for bullies.
But the thing that bugged me most was that I had a small dick. When it's erect it's still only about three and a half inches long, and only as big around as a quarter. I didn't tell a soul. Probably some doctor found out during some exam -- I forget -- but that was it. I never told anyone in my family or any of my friends.
My family situation wasn't so great. My father was a great guy, an endocrinologist working for a pharmaceutical company. But he wasn't very ambitious. He didn't want to try to climb the management track, and in fact he took a new job that let him do really cool research even though it paid less. But my mom wanted more. She wanted more expensive things and vacations. She used to work as a technical writer and made good money. She quit when my sister Alexa and I were born, but she never went back to work even when we got to be school age. My father said that if she wanted more possessions, she should work too, and not expect him to become a manager and do stuff he hated.
My mom didn't like that idea and took off with another guy, and by the time I was 13 my folks were divorced. The other guy was a successful businessman, but he never had kids and didn't want to be troubled by them. Mom went along. Dad was happy to get custody of me and my sister.
What hurt me and really hurt my sister is that it didn't seem to bother mom much to lose us. Maybe it was partly being mad at mom that made Alexa do the terrible thing that changed my life. But it was still her fault.
I woke with a start one morning when I felt the covers being pulled down, and then I heard her giggle. I don't wear anything below the waist at night, and I had a morning hard-on. And there it was, all three and a half inches of it, for Alexa to see. And she giggled.
"It's so tiny!" she said, gleefully.
I grabbed the covers to hide myself again. I was too mortified to yell at her. I just turned beet red and stammered.
"The ones in Ellen's movies were way bigger!" She skipped off then, giggling.
Alexa is thirteen, a year younger than me and just starting high school. She used to be nice sometimes, until puberty got hold of her.
We were sitting around the dinner table that night. And then Alexa did the thing I'll never forgive her for as long as I live. Alexa said out of the blue, "Hey dad, did you know Evan's got a really tiny penis?" I had been hiding my little penis from everyone, my father more than anyone else.
But my father didn't smile at my sister's remark or give me a condescending look. He froze, and then fixed Alexa with an icy stare.
"And just how do you know that, Alexa?"
"Ummmmm..." she whispered. She knew she was in trouble.
"Did Evan tell you?" One glance at my flushed face told him the answer to that.
"Answer me, young lady!"
Alexa started crying.
"Cry all you want, but answer me! Answer me!"
"I ... pulled the covers down on his bed while he was sleeping."
At first my dad was white with rage, but he controlled himself.
"Have you told anyone else?"
"No," Alexa replied. I thought I detected the slightest pause before she answered.
"You must never tell anyone else, do you understand?"
"Yes, dad," Alexa said.
I was miserable. Now my dad knew I wasn't going to grow up to be a real man. I had let him down. I knew at one level that was crazy thinking, but it felt that way.
We ate dinner in silence. Towards the end of the meal, though, dad smiled to himself.
A week passed, and whenever I thought of Alexa and how she had pulled down the covers I got this sick feeling.
I felt furious every time Alexa crossed my sight, and now and then I found myself accidentally stepping on her foot or jabbing her with my elbow. She knew better than to fight back.
"Evan," my father said, "Let's take a walk."
"OK," I mumbled.
He's not a real chatty guy, so it was no great surprise that we walked a couple blocks before he said anything.
"I've got a secret to tell you. You're old enough now to keep secrets, right?"
"Right," I said, with a tingle of pride. I guess I had passed a milestone of maturity in his eyes.
"I've got a pretty small penis too. And I know what it's like."
My mind reeled. My dad was a wimpy half-man too? I had always admired him. But then, on the other hand ... he understood! And it wasn't my fault so much. It came down through the genes, maybe.
"When the other guys found out..." he said, trailing off. "Well, things are a lot better now, though, right? They don't let bullies get away with things any more, right?"
"I guess." I didn't know how things were in his day, so I didn't have a standard of comparison. I knew there were kids who were really cruel to the ones who weren't cool.
We walked on in silence a bit.
"How much have I told you about what I do at work?"
"Not much. Something with chemistry, right?"
"True. I don't talk about it much because it's all secret, see.
"I work on drugs affecting women's bodies, like their periods and stuff. The drugs we want to make and sell some day are contraceptives, and drugs for when girls don't start getting their periods or get them too early. Then we want drugs for the other end when they get to menopause, and all kinds of troubles in between. But I'm not involved with making any of those drugs. I do more basic research, producing components that can be mixed up to do different things.
"I've got this lab in the basement. It's for when I want to do work on weekends and don't want to go in to the office."
I was dimly aware that there was a locked room in the basement that I had never been in, but there was stuff against the door and it looked like no one went in there for months at a time.
We talked about other things for a while, but when we got back to the house he led me down to the basement. The path to the locked room had been cleared, and a new lock installed -- just within the past couple days.
"Two, four, one, one, two," he said slowly, punching in each digit.
"Two, four, one, one, two," he repeated under his breath a few times. "I'm still trying to make sure I know it by heart."
I knew that he wanted me to be able to remember those numbers, and I made sure I did.
The room featured a refrigerator and a table and just a few supplies.
He opened the refrigerator, which contained a number of little bottles labeled with just a single letter, like "A". Then he showed me a notebook. There was a section for each letter describing what the stuff in that bottle did.
"When a woman or girl inhales a mixture of these, it can have an effect on her. Depending on what you put in, different things will happen. The more 'B' you add, the longer it takes for the drugs to start working. The more 'C' you add, the longer it lasts. 'A' is a marker. Sometimes a girl might not be sure whether she's gotten enough of the drugs to have an effect. 'A' makes her face flush briefly so she can tell. And then there is 'Z'. 'Z' is very important because it makes any of the effects of these drugs go away."
"What do the drugs actually do, I mean the other ones?"
"Well, 'M' is pretty good for making menstrual cramps go away, and 'N' makes a period start when it's late. 'O' keeps a period from starting for a couple days. The others do other different things."
"Interesting," I said, not feeling particularly interested.
"It's like my own private chemistry set," my dad continued. "But don't tell Alexa this is here, right? She's not old enough to keep secrets like this. And, well, there's the question of what an unfortunate combination of those drugs would do to her! The room's got a lock, and only I know the combination..." I thought I saw him give me a significant glance, "but still! Well, enough of that! Now you know a bit more about my work."
And with that, my special time with dad was over.
I tried to figure out why my dad had been showing me that stuff. Maybe he wanted to make me feel more grown-up to compensate for having a small dick. It was a nice effort.
As I was drifting off to sleep that night a number of thoughts converged. I had a small dick. My dad did too, and he had been furious at Alexa when he found out what she had done. He had recently set up a chemistry set in the basement. He had let me see the combination. I had the feeling I was invited if not even expected to go down and look around. Making yucky periods start or stop or whatever wasn't very exciting, but there were those other letters he hadn't explained. It was worth a look.
Alexa had afternoon soccer practice, and dad didn't get home until 6pm at the earliest, so I had the house to myself in the afternoon. I decided to check out the chemistry set.
'This factor in tiny doses can help reduce pain in the breasts from hormonal shifts. Beware that with a larger dose the breasts will become very itchy, although there is no permanent harm.'
'This factor when combined with a man's sweat causes an effect to occur only when the woman smells that particular man.'
I smiled. These were more interesting than period starters and stoppers!
'This factor causes a woman's vulva and vagina to engorge and lubricate as they would with sexual excitement.'
I got a hard-on reading that one!
'This factor can help with incontinence. However, in larger doses it can make it very difficult for a woman to urinate.'
Oh boy, I knew that playing with this chemistry set was going to be good. Very sweet!
Once again I seethed as I recalled Alexa laughing at my small cock, then casually mentioning it to my father at the dinner table.
I was motivated to learn chemistry as never before, and read the details about doses, mixing, how long the concoctions lasted at room temperature, and so forth.
In retrospect, maybe I went too far. Maybe I went totally apeshit over something that shouldn't have been such a huge deal. But my father encouraged me. Maybe what happened to him when he was a boy was so horrible it made him totally crazy on the subject. In any case, Alexa paid a steep price. And I loved making her pay.
"Hey, sis," I said. "Take a whiff of this!" I put a cotton ball under her nose.
"Mmmmm, smells nice," she said. "What is it?"
"Never mind," I said. "It's a secret."
Alexa shrugged, but as she did her face flushed red briefly.
The next afternoon when Alexa came home from school, she looked a little preoccupied.
"Hi, sis," I said. "You look a little down. What's wrong?"
She looked at me. "Nothing's wrong," she said, but it didn't fool me.
"Well, you know you can always tell your big brother what's on your mind."
She looked at me strangely, undoubtedly noting that I wasn't usually that friendly.
The next day at breakfast she looked worried.
She got home late that afternoon, looking disheveled and dazed.
"What's the matter, sis?" I asked, voice full of caring concern.
"None of your business!" she shouted and stormed off to her room.
I knocked on her door, but she yelled, "Go away!"
"Alexa, is there is some kind of female trouble you are having?"
The door flew open. "What, is it all over school?" she asked. "Nurses aren't supposed to talk," she continued, half to herself.
"I am pretty sure I know how to fix it."
"What? How do you know that? Did you do this to me?"
"Who, me?"
"You did! You did it when you had me sniff that stuff yesterday."
I smirked.
"How did you manage that? I'm going to tell dad."
"Be my guest," I said. "But if you sniff this stuff the problem will go away."
"OK," she said suspiciously.
She took a sniff, and her face flushed red briefly.
At supper, Alexa seemed relaxed again, at least physically.
"Dad," she said. "Evan gave me some drug."
"And what makes you think that?"
"He had me sniff something yesterday, then I had a problem, then when he had me sniff something else the problem went away." "Oh, I'm sure it was just a coincidence," Dad said.
"No, it wasn't!"
"Alexa, you're being silly!" he said with some force, and she dropped the subject.
The next afternoon, she approached me again. "Do you have more of that stuff?" she asked.
"I think I can find some, yes."
"Give it to me!"
"That's no way to ask, sis."
She took a deep breath, "Could I please have it?"
"Why do you want it?"
"I just need it, OK?"
"No, I think you owe me an explanation."
"What is that stuff? How did you get it?"
"I didn't say I was going to explain anything, I said I wanted you to explain."
"No!"
"OK, I said, heading down the corridor to my room.
"No, OK, wait!" she said.
"Let's go into your room to talk," I said.
We sat on her bed a few feet apart. "This is so embarrassing," she said after a pause. "Couldn't you just do a favor to your little sister? I've been a good sister, haven't I?" She hesitated.
"I'm ... I'm sorry about pulling your sheets down," she said.
"That's nice," I said, making no attempt to hide my sarcasm. "But still, you need to tell me what's going on."
She sighed. "I started having trouble peeing. It was so hard to get it out. The next day I could barely pee at all; I went to the nurse at school, who sent me to the gynecologist. And she examined me -- God, it's so embarrassing. First she got a little tube, and shoved it up inside..."
"Where, inside?" I asked.
"You know, where the pee comes out! It hurt a little but once it was up there the pee flowed out and it was a huge relief. You're not going to tell anyone, are you?"
"Alexa, did you tell anyone about my small dick?"
"Dad told me not to, and I knew he meant it, so I didn't."
"What about during the day before you told him?"
"No, no one!" she said, but I knew her tone of voice.
"Who?"
"No one!"
"I know you're lying. Who did you tell?"
Alexa looked miserable. "Well, I may have said a little to Ellen, but she swore she would never tell another soul, and I'm sure she didn't!"
"Hmmmm," I said. Ellen was a popular girl with a wide circle of friends, so it was probably all over the school.
She continued the story. "That's when you offered me a whiff of that stuff, and within a half an hour it was all better!"
"That's nice!"
"But it's getting worse again," she said.
"Did the doctor say what it was?"
"No, she said it was a mystery."
Alexa was lying again.
"Any follow-up appointments?"
"No."
"This is the first time I've ever heard of the doctors just giving up when something really serious happens, like when a little girl can't tinkle in the potty any more."
Alexa started crying.
"Please, Evan, please? I'm so sorry about telling about your dick."
"Sometimes 'Sorry' isn't enough! Keep talking."
She was silent, and I started to get up to leave.
"No, wait!" she said, miserable. "The doctor says when that happens it's always because ... Do I have to tell?"
"Yes."
"because a girl's been playing with herself too much, and if she takes a rest from it then it will get better!"
I started laughing. Dad's book said that it 'mimicked the symptoms of urinary blockage from pathological masturbation'. Right on the nose! I pointed at her and laughed some more.
"It's not funny, Evan! Please! I wasn't playing with myself at all!"
"Yeah, likely story," I said, chuckling and shaking my head.
"Maybe a little, now and then, but just a few minutes, not all night! And not since I first got this problem!
"So I told, now can I have it? Please?"
"I don't know, Alexa, you're a naughty girl, diddling yourself all night long."
Then Alexa just let down all her defenses and sat crying, like a little girl: alone, miserable, and hopeless.
I don't know why, but I took pity on her then. I had poured a few drops of Alexa's medicine into a small bottle in my pocket. Holding it firmly in my hand, I reached out to her. She eagerly put her nose over it and inhaled deeply twice, before I took the bottle back.
"Can I have that?" she asked.
"I don't think so," I said.
Alexa moaned, and I went back to my own room.
In about five minutes, I heard her head to the bathroom, and as soon as she shut the door I walked quickly and quietly to the door. Through the closed door I heard pee flooding into the toilet and a little sigh from my sister. I called through the door, "Wow, I bet that felt good!"
"You pig!" she shouted.
After she reappeared, I said, "That wasn't a very nice thing to say to a guy who just helped you feel a lot better."
"I'm sorry," she said curtly.
"That didn't sound very convincing," I said.
She repeated, "I'm sorry" under her breath as she strode to her room and slammed the door behind her.
The next day Alexa was home early, evidently having skipped soccer practice. Knocking at my door, she looked pale and was fighting back tears. "I tried telling them you were drugging me, and they just laughed at me," she said. "Evan, I'm so sorry for everything bad I've ever done to you. I'm really, really sorry for looking at your dick. I'll do anything!" she said.
This was a good start. My bratty little sister was begging. But there was far more humiliation in store for her. "First, why don't you show me what this problem looks like between your legs."
"Evan!"
"Well, you looked at me without my permission, so this seems only fair."
She saw the logic in that, though she didn't like it one bit.
"It doesn't look any different than usual! I just can't pee!" she said.
"Well, I don't recall I've seen your private parts lately, sis. Maybe you've got a huge pussy, big enough to drive a truck into, and I can laugh at that!"
"I do not!"
"Well, show me."
Alexa gave a frustrated groan. Soccer shorts and panties came down as she stood. She briefly spread her labia, pointed, and let them slide together again.
"No, no, I think you need to sit here on the bed, spread your legs wide, and give me a good, long guided tour."
She sat and held herself open, trembling and looking away in shame. I had never seen a naked girl before, except maybe little girls with the tiny flaps shut and hiding the mysteries within.
"Have you gotten your period yet?"
"Yeah, for about a year now."
"So you're all grown up down there, like a woman?"
"I don't know!" she said.
"Why don't you show me where everything is?" I asked.
She mumbled, "That's where the pee comes out, and that's my vagina," she said quickly, pointing to each in turn. "And that's my clitoris," she said quickly and quietly.
"Hmmm, can I touch?" My little cock was growing in my pants.
"No!" she said, indignantly. "I didn't touch you!"
"That doesn't matter. You said you'd do anything."
She paused, now pink with shame.
I saw her shame and remembered my own. "There is one thing you haven't apologized for."
"I'm sorry I pulled the covers off and looked at you. And I'm sorry I said anything to Ellen -- though I'm sure she didn't tell anyone!"
"Nice start," I said. "You're forgetting something."
"What?"
"Telling dad."
"Oh," she said. "He knew, didn't he?"
"No, he didn't. Why would he know?"
"Well, you're both guys, right?"
"Just because we're both guys doesn't mean we show each other our cocks."
"Oh," she said quietly.
"And you know how that makes me feel that dad knows about my cock? SHITTY! That's how!"
I felt a surge of shame. This was getting away from me. I was here to humiliate Alexa, not humiliate myself.
"Oh, no," Alexa said, with genuine mortification. "I never thought of it that way."
I reached over to touch her pussy, and she didn't stop me. I rubbed her labia, poked at her vagina, and a finger went in. I kept pushing gently, and it kept going in farther and farther.
"That's where the tampons go, right?" I asked.
"Yeah," she said. "My vagina."
"Hmmm. What's a vagina used for, Alexa?"
"You know that!"
"Oh, maybe, but I want to hear it from you."
She sighed. "Well, it's where babies come out, and where the menstrual blood comes out." She hesitated briefly, "And where the sperm goes in."
"How does the sperm go in, Alexa?"
"Oh, Evan!" She sighed. "You're making fun of me, aren't you."
"Yes. Continue."
"A penis goes up inside and the sperm comes out the end."
"Has any penis gone up your vagina?" I asked.
"No!" she said.
I moved to her clitoris, which was prominent, and started stroking it gently.
"And what's this good for?" I asked.
"Nothing, really," she said, gulping.
"Nothing?"
"Not really!"
"Then you wouldn't mind if the doctor removed it, like an appendix or something?"
"No," she said, groaning. "It's for pleasure."
"Whose pleasure?"
"Mine, of course!"
"Let's not get snippy. So, does it feel good now?"
"Not really," she said.
I kept rubbing, over and over.
"Well, maybe a little," she said.
I rubbed faster.
"Haven't you touched enough yet?" she asked, decidedly uncomfortable.
"No," I said. With my other hand, I poked a finger into her vagina again, and slid it in and out.
My little cock was completely stiff.
"Oh, my!" I said. "Your pussy is getting all wet! I wonder why that's happening."
"I don't know," she said, feigning innocence.
"I think I remember from sex ed."
"What?"
"That means your body is getting excited and wants a prick up inside!"
"I do not!"
"Maybe you don't, but your body does."
I kept rubbing and thrusting.
"Man, this is like a river here! You're sure you aren't peeing? You sure are making a mess!"
"Evan," she said quietly, "Please?"
"Evan," she said with tears in her eyes, "We're not supposed to be doing this, right? It's incest, right?"
"You should have thought of that before you told about my dick." I had another thought. "Yeah, it's incest, but you slutty girl, you're getting all hot for your brother's cock! You want it?"
"Evan!" she whimpered.
Incest. What did I think of incest? I had never thought of Alexa in a sexual way before, but something had changed. I had started poking around in her pussy to humiliate her, but once I started messing around with it, my body knew it was just like the kind of thing my body wanted to fuck.
"Can I have a sniff yet?" she asked meekly. "I've really gotta go, and I can't! Please?"
I was rock hard in my pants from watching Alexa get all soupy, and I had an inspiration. Alexa knew what my cock looked like, so I might as well show it to her again. There were definitely possibilities here.
"Not quite yet," I said. I stood and casually pulled down my jeans and briefs and stepped out of them.
I stood in front of her.
"You've seen this before. Apologize to my cock for calling it small," I said.
Alexa looked miserable again. She addressed my organ from six inches away. "I am sorry for calling you small."
"Kiss and make up?" I said.
Alexa looked at me with a flicker of disgust, but she approached my cock and kissed it.
"What about a nice, long French kiss?"
She knew she had no choice, so she took me in her mouth. I had never had a mouth around my cock, of course. I wasn't cool enough to get blow jobs at school, and even if I had been, I wasn't going to be the laughingstock of the entire place when I pulled out my tiny cock.
Whatever Alexa was doing felt great! I especially loved the roughness of her tongue flicking back and forth on my tip. My dick may be small, but it feels plenty of pleasure. I was panting and moaning.
"Is that enough?" she asked.
"No!" I said. "Keep doing it! Actually, wait!"
I lay down on the bed. I didn't want to worry about falling over when I came.
Alexa went back to her job. And it felt great.
I had always dreamed of burying myself in a warm, wet cavity in a girl's body. While this hadn't been the cavity in my fantasy, it felt pretty fantastic.
"Oh, just like that, sis!" I moaned.
My climax was upon me before I knew it. I arched my hips upward while my cum boiled out of my prick in shots.
Startled, Alexa took her head off to deal with the strange stuff in her mouth.
"No! Keep going!" I said urgently.
But she just sputtered and spit as my later spurts landed on my chest.
"Yuck!" she grumbled. "Gross!"
My cock would have preferred to finish unloading in a warm, wet place, but I still felt very good. I lay panting on the bed, eyes closed.
I lazed a minute, catching my breath.
"Listen, baby sister, the cum that spurts out of my prick is the most wonderful, precious stuff there is, and it's your job to lick it all up and swallow it. You can start with what's on my stomach now."
She didn't answer, so I opened my eyes. She was on the floor rummaging through my jeans pockets. Sneaky bitch!
I dragged myself out of my orgasmic stupor and launched myself at her, tackling her just as she had grabbed the vial. My sticky stomach was plastered against the back of her soccer jersey. I tried to pry the vial from her fingers.
"Let go, Alexa!"
"No! Please let me have it!" she whined.
"Let go now, or you'll regret it," I said calmly.
She didn't let go. I jammed my hand between her legs, grabbed whatever fleshy bits of her pussy were sticking out to be grabbed, and squeezed as hard as I could, digging in with my fingernails.
"Ouuuccch!" she cried, letting go of the vial.
I sat back and took a breath.
"Oh, Alexa!" I said. "You are very bad again! Taking something that's not yours! Going through my jeans without asking!"
"Oh Evan," she wailed. "I'm sorry! But I need it!"
"That's no excuse for that kind of behavior!" I said, then continued more calmly, "If you just stop masturbating all night long, I'm sure it will get better, like the doctor said!"
"I haven't touched myself!" she cried.
"You're not going to let me have any, are you?" she asked, crying.
"No, not now!"
"What am I going to do?"
"I imagine you will go back to the doctor, who will drain your pee for you and tell you to stop playing with yourself -- you nasty girl!"
"No, please!"
"Maybe I'll give you some. First, bend over my lap."
"What are you going to do?"
"If you ever want to get any of that stuff again, you'd better stop asking questions and do what I say."
She bent over, teeth clenched, and I pulled her panties back down to mid-thigh. I spanked her hard, whapping one blow after another.
I growled under my breath, "Here's for peeking, here's for laughing, here's for skipping as you left, here's for telling dad," at which point I gave her three massive whacks. "Here's for telling Ellen, here's for calling me a pig, here's for not letting me spurt all my cum into your mouth, here's for spitting it out and sounding disgusted, here's for looking through my jeans without asking," followed by one giant massive whack, "here's for not giving it back, here's for whining and begging."
By then her backside was very red and bleeding in a few places, while more blood seeped from where I had crushed her pussy in my fingers.
"And here's for not apologizing," I said, whacking away. "I'll keep spanking you until you apologize."
"OK," she sniffled, "I'll apologize!"
I rested my right arm and hand, which was a bit sore itself from all the punishment it had doled out.
Alexa spoke with her bottom still in my lap, bright red and ready to receive more punishment as I saw fit. Her head was on the floor, cheek against the carpet.
"I am sorry for sneaking into your room and pulling the covers down. I am so, so sorry I did that!..."
"I'll bet you are," I said. "Sorry because I'm making you pay, or sorry because of what happened to me?"
"You! You! I'm sorry about what happened to you! I'm sorry for invading your privacy and finding out your secret."
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