That's what Big Sisters are For

I kept grinding into my sister. I hadn't gotten off yet, but I was close.

"OH!" Darcy cried out. She arched her crotch upward and I felt my dick slide back. Suddenly, my very bare cockhead was resting right at my sister's very bare pussy. I could fall forward a centimeter and be sheathed in her snatch.

Darcy whispered in my ear. "Put it in."

What?

I stopped in place.

"Put it in me. Please," Darcy said. She looked at me with wide, wanting eyes.

The reality of what we were doing - who I was with - rushed over me like ice water. I was humping my sister. My sibling wanted me to have sex. My dick shriveled down to nothing. I rolled off to the side.

Darcy seemed to immediately see the change in me. She hugged me close.

"We can't do that," I said, "That's sex. You said we can't have sex."

"It's alright," Darcy said, "I want it real bad and I know you do, too."

"Are you even? I mean, do you take the pill? Or whatever?"

Darcy bit her lip. "I trust you," she said quietly.

"We can't do that," I said, "You said it was wrong, Darcy. It's wrong. We shouldn't. Fuck, we're not supposed to be doing any of this."

My sister lay back shellshocked. I grabbed my clothes and put them on. I felt icky, literally gross. I went upstairs and got in the shower. All the things we'd done came racing back to me. I couldn't get them to go away.

When I got out of the bathroom, Darcy was waiting for me. She was fully dressed. "Ethan, I'm sorry," she said. "I got carried away in the moment. You weren't ready for..."

"Ready? How could I ever be ready for that?"

Darcy winced. I'd clearly hurt her feelings. She took a deep breath. I saw her face go stony. "You sure seemed ready for all that other stuff," Darcy said. "You're supposed to be different. But you're like every other boy. You only care if you get yours."

"Darcy, I..." My sister's sudden change of tone surprised me. I hadn't expected her to fire back, and now I found myself unprepared. "That's not true," I said. "I love making you... Well. You know. It's amazing."

"But it's wrong," Darcy said.

"No! Well, yes. I don't know. Fuck," I said.

Darcy took a deep breath. "OK, I know you're new to all this stuff and it can be scary," she said, "But that's why we're doing it. So you can be ready for a real girlfriend. Like Victoria from the lingerie store. She's going to expect you to take care of her and I'm showing you how. I'll take the lumps for now, but I expect you to learn."

I nodded. "I'm sorry, Darcy."

"Me too," my sister said. She kissed me on the forehead, then stepped away. We searched each other's eyes for a moment.

I heard the front door open as my parents came home. At least we're both dressed, I thought. Darcy walked past me and into her bedroom, shutting the door behind her.

That night, after dinner, Darcy came into my room like always. We acted like it was all the same, but it wasn't. She gave me what I can only describe as a cursory handjob, then stood up stiffly. I offered to return the favor, but she waved me off.

"I have to get up early for work," Darcy said, "So I probably won't have time to help you tomorrow morning."

"Tomorrow's Sunday," I said.

"I know. It's some emergency thing," Darcy said, "I'll be back as soon as I can."

I felt a strange sadness well up in my chest as my sister switched off the light and left my bedroom.

*

The next morning, I woke up to my cell phone screaming at me. I picked it up and saw that my sister was calling.

"Ethan, thank God," Darcy said when I picked up. "I have a serious problem."

"What's wrong?" I asked, groggy. My first thought was that she'd been in an accident and it made me almost nauseous with worry.

"My work computer crashed, and it wiped half my hard drive. The techs say they can get it back, but I've got a meeting in five and I can't wait that long. I need the Anselmo Case file. It's in my backup storage on the laptop in my bedroom."

I popped out of bed and raced over to Darcy's room. I opened the door, phone in my hand, and went straight to her desk.

"There should be a thumb drive in the laptop, you see it?"

"You want me to bring it over to you?" I asked, "I could probably borrow Mom's car."

"Not enough time," Darcy said, "Just turn on the laptop." She gave me her passcode and had me go into her e-mail and send her the file.

"Thanks, bro. You're a lifesaver," Darcy said when the message came through, then hung up. I sat back in her chair, exhausted. I'd just gotten up and I already felt like going back to bed. If that was Darcy's job on a Sunday, I was happy to be in the mailroom.

I looked at her computer screen, dumbly. It had the standard green field and blue sky that came with Windows. The desktop was almost completely clear. A few programs, the usual icons, and one folder dragged to the middle. It was labeled 'E.'

I told myself to shut down the computer, but my curiosity got the better of me. After all, the folder had my name on it. Right?

I opened the file. My eyes went wide.

*

I waited until Darcy came home. It was another super late night for her, and she didn't show up till well after my parents had gone to bed. I saw her headlights scan down our sleepy street. Heard the door as she came inside. I stayed still, in the dark, sitting right at my sister's laptop.

Darcy came upstairs. I heard her check my bedroom, then she opened her own door. She saw me sitting in her chair and jumped.

"Sorry, E, I didn't expect you in here," she said.

I didn't reply. I took the laptop off the desk and showed it to her. My sister looked confused, then certainty filled her face. Anger and a bit of fear.

"You went through my private stuff," she said.

"It was an accident," I lied, "When you asked me to go into your email, I opened it by mistake."

My sister stayed standing, staring at the laptop screen. I knew what she was looking at. I'd spent all day going through it myself.

The 'E' folder was porn. Lots and lots and lots of porn, enough to dwarf even my own comprehensive collection. Unlike mine, though - which had a variety of different fetishes and themes to fit my many different horny teenaged moods - my sister's smut was centered around one specific thing: incest. Brother/sister incest.

She had videos of supposed siblings, movies, captioned pictures, audio recordings, short stories, full novels - all of it. Any kind of porn you could imagine, she had it, and it all featured siblings doing the one thing they're not supposed to do together. The very thing I'd been doing with Darcy.

"How long?" I asked.

"What?" Darcy asked absently.

"How long have you had a thing for me?"

"I don't have 'a thing' for you, Ethan," Darcy said, hotly.

"This whole time you've been acting like it was a mistake, or luck, or you taking care of me," I said, "But that's not it at all, is it? This has been about you fulfilling your weird fantasies."

Darcy didn't say anything. She was wearing a pink and white whorled sleeveless dress. Professional for her big meeting that morning, I supposed. The laptop was the only light in the room.

"So, you've, like, always had a crush on me," I said.

"No, Ethan," Darcy said, "This isn't about you. I mean, not really."

I gave her a dubious look.

"I mean, you're cute. Kind of. Especially since you've started working out and dressing up. But if you were just another boy, there's no way I'd be attracted to you."

I had to admit, of all the reactions I expected, Darcy's personal attack wasn't one of them. I told myself it didn't hurt, but it did.

My sister sat down on her bed and motioned for me to join her. "Look, I'm sorry that you found all this. That it gave you the wrong idea. God, this is hard to explain. I don't get turned on by you."

I made that wounded puppy dog face again.

"Look, the thing that gets me going?" Darcy said, "Is that you're my brother. That's what makes it hot for me. That's what turns me on."

"Incest," I said.

"Brothers and sisters," Darcy said. "Nothing else."

I almost laughed, how she said it so casually. Like what she was into was totally normal and everyone else was the weirdo.

"I don't get it," I said.

"I don't either?" Darcy said. "I can't help how I'm wired. When I found these things, I realized they turned me on. Like, really. And the more I found of it, the more I liked it. Look, Ethan, don't be hurt. I guess you're handsome in your own way. I mean, that girl at the lingerie store was really into you, I could tell. But for me? It's because you're my brother that makes it hot."

"So, if I was a dude on the street and some other guy was your brother, you'd be into him?"

Darcy shrugged. "Probably."

"Darcy, that's weird," I said. Again, I was speaking before my brain could vet the words.

"I know," Darcy said, "But it's me." She stood up, took her laptop out of my hands, and carefully put it back on her desk. "You have to admit you've been having fun."

"It was," I said, "It is." I couldn't believe I was saying this. Was I actually trying to keep my semi-sexual relationship with my sister?"

"See, you kind of get it," Darcy said, "You're acting all ashamed, but the truth is you like it, too."

I nodded. I couldn't lie to my sister. Maybe a week before I'd have felt differently. But in that moment, I wasn't going to let it go. At least, not completely.

"So, you still want me to wake you up in the morning," Darcy said. She gave me a coy smile.

"I want to wake you up, too," I said, accenting the word 'wake.' "But we can't have sex."

Darcy's face went from grin to grimace in a second.

"That's a different line, Darcy," I said, "I don't think we should cross it. Even if we want to, it's too strange. And dangerous."

"Lots of other siblings do it," Darcy said.

"Fool around?" I asked. "Yes, I bet they do. It's probably natural when you're young and horny and there's a girl or a boy right there. But actual, total, full-on sex? There's no way. I mean, it's illegal."

"Yes, they do," Darcy said. She was pouting now. "Brothers and sisters have sex. All the time. And I can prove it to you."

"I'm pretty sure those videos are fake," I said, "And those stories are written by creepy, loveless virgins and old pervs."

"I can prove it," Darcy said, "With real people that we both know."

"OK, seriously?"

"Sam and Dave," Darcy said, she sat back, arms crossed, like she'd won the argument.

"You mean the gay couple down the street that just adopted that really cute Asian baby?"

"No! Samantha, my friend from high school. You remember Sam?"

I did remember her. She was blonde and cute, though way less curvy than my sister. She had a real 'girl next door' look to her and I'd had a bit of a crush. Of course, I was 16 at the time, I had a thing for every one of my sister's high school friends.

"Right, so her and her brother David," Darcy said.

"They fool around," I said.

"They have sex," Darcy said, "All the time. They could be doing it right now for all I know."

I raised an eyebrow, but I didn't say anything. The 'prove it' was implied.

"Fine," Darcy said, crossing her arms under her breasts. "I'll show you."

"Uh huh," I said.

"I will," Darcy said, "I just need a little time to figure out how."

"OK," I said. I pictured her at a casting agency trying to hire actors. Or forging a signed affidavit. There was no way my sister was going to convince me that Sam had sex with her brother.

"And to show you, no fun stuff till I do," Darcy said. Then she threw me out of her bedroom.

*

The next morning, I woke up with the king of all hard-ons. I lay back, waiting for my morning appointment, but my sister never showed. Worse, I tried to stroke it myself and found that it wasn't even all that satisfying. I gave up before I climaxed. It wasn't worth it.

I saw a text from Darcy telling me that she had to head out early and I was on my own for getting to work. I rolled out of bed and went for my morning run, then showered and got dressed for work. I took the train into the city, not a bad ride, and was in the office with time to spare.

I went over to Darcy's cube, but my sister wasn't there. I had lunch by myself, as well. Then I went home and cooked dinner for the family. That night, again, I stayed in bed and waited for my sister to show up. But when she did, she went straight to her room without even saying goodnight.

"Are you two fighting?" my Dad asked over breakfast the next day.

"I don't know," I said, honestly.

Three days went past like that, to the point where I started to wonder if my dalliances with Darcy had all been imagined. What made more sense, that my sister had started doing dirty stuff with me and stopped, or that it never happened in the first place?

Then, in the middle of the workday on Wednesday, my sister came and found me in the mailroom. I worked with two other guys, both in their fifties, who liked to listen to Howard Stern extra loud and talk about girls they'd nailed at truck stops. They nearly lost it when Darcy showed up in the doorway.

"That's my sister, guys," I said.

"That's sex on legs, dude," one guy responded, even though my sister was standing right there. She gave him a tight smile.

"We need to talk," Darcy said to me. I nodded. I braced myself for the breakup speech. How had I ended up in this place where I was actively, actually worrying that my sister was going to stop forcing me to have sex with her? "Something's come up at home that we need to deal with. I already spoke to my boss and yours. We need to leave right now."

I looked over at the other two guys. They shrugged and went back to filing. As soon as I was out in the hallway, I accosted my sister. "What's wrong? Are Mom and Dad, okay?"

"Pfft, they're fine," Darcy said. She started walking down the hallway to the elevators. "I needed an excuse to get us out of here early. 'Personal emergency' was both appropriate and accurate."

"So, there's nothing actually wrong," I said, following my sister a few steps behind.

"I need to get laid," Darcy said, "That sounds like a personal emergency to me."

We went down to the garage and got in Darcy's car.

"You want to drive?" Darcy asked.

I was about to kneejerk a no, but I saw the look in her face and recognized the peace offering she was giving me.

"Sure," I said. I was able to get us out of the garage without incident and only stalled once on the way to the highway.

"You're getting way better at this," Darcy said.

"Thanks," I said, accelerating past a slow-moving truck.

"You're getting way better at a lot of things," Darcy said. I looked at her body and gave her a saucy smile. "Not that. Well, OK, that too. No, I meant, like, the life stuff. You've run every morning this week, haven't you?"

I told my sister that I had.

"You're eating better. Your cooking is almost edible. You stopped smoking pot. You're turning into quite a catch, little brother. Good thing I've already got you in my net," Darcy said, "Although if you want to call that Victoria girl from the lingerie store, I'm willing to let you. With certain caveats, of course."

I decided that this was Darcy's weird way of trying to give me a compliment, so I thanked her for it.

"You're welcome," Darcy said, "You're the one who's doing all the work. I had to give you a little nudge, that's all. I know the last few days have been hard for you, but I promise the payoff will be worth it."

I looked at my sister and paused. To this point, I'd assumed we were on some mid-afternoon nookie run. Suddenly it occurred to me that she might have something more planned. After all, since when did Darcy need to leave the office to suck me off?

"We can't have sex, Darcy," I said.

"You're going to love this," she said, "You'll see."

I felt my stomach churn a little. Amazing how much a car, a vehicle speeding down the road at 70mph, could feel so much like a cell.

"And after?" Darcy said, "I've been thinking. My office and your school aren't far from each other at all. If we live together, we could probably spring for an apartment, you and me. Wouldn't that be awesome?"

I pulled off the highway and turned down the road to our house.

"Turn left up at the light," Darcy said.

"That's not the way home," I said.

"We're not going home," Darcy said. I tried to think of all the random places my sister might try to give me a blowjob. A convenience store, a bar, a playground, a library... They all seemed so implausible. Which only made them all likely Darcy sex sites.

My sister had me turn us onto a suburban road and I realized I recognized where we were. This was the other side of town, one of the more upscale neighborhoods. When had I been here before?

"Sam's place is right up on the corner," Darcy said, "So you should probably park here. Don't want to be too obvious."

Sam. Samantha. As in Samantha and her brother Dave. The ones my sister swore were secret sibling sex buddies.

"We're going to Sam's house?" I asked. The knots in my stomach twisted around each other. I was running out of intestines to bend.

"Duh. This took a lot of doing, so don't screw it up," Darcy said. She took my hand and led me down the street.

Sam's house was one of those McMansion places that were built in the early aughts before the economy went down the tubes. The whole neighborhood was one big house next to the other till the scale got messed up and you thought it all looked normal. Like seeing a parking lot full of Hummers, a relic from another era, yet no less impressive.

My sister led me across Sam's well-manicured front lawn and around to the back of her house. There was an inground pool and a small patio with a barbecue set that cost as much as a new car.

Darcy pulled at the sliding glass door and it opened easily. She put her finger to her mouth.

"Do they know we're coming?" I asked, staying outside.

"Sam does," Darcy said, "Dave doesn't. Come on, we have to hurry, or all my work will be wasted."

The house seemed empty. Our footsteps echoed. We walked through the massive kitchen and up the stairs. On the walls were multiple pictures of a happy family through the years. I recognized Sam in them and realized that her whole family had the same exact nose and mouth. They looked less like relatives and more like strange clones of each other. It was unnerving.

Down the hallway, Darcy led me back to a boy's bedroom. It was painted grey with walnut furniture. A couple of sports trophies sat on one of the dressers. There was a closet on the back wall with slatted, white, wooden double doors.

Darcy threw open the closet and pushed me inside. She followed after me. We were covered in heavy coats, standing on old shoe boxes, but there was enough room for both of us. More importantly, we could both see out of the slats and into the boy's bedroom.

I started to ask a question, but Darcy shushed me. We stood there, silent, staring at the empty room. The closet started to feel hot. It smelled of mothballs and old leather. I felt like a criminal.

I heard the sounds of heavy footsteps. Then voices. I recognized Sam's immediately.

"No, your room," Sam said.

The door popped open and two twenty-somethings fell into the room, wrapped around each other. They were kissing like it was the only way to get oxygen. The room filled with the sounds of gasping mixed with wet smacks.

Sam was even prettier than I remembered. Her body had filled out some, but she was still straight as a board compared to Darcy. There was no doubt that the boy she was kissing was her brother. He had that same family face. Their hair was even the exact same color.