Here’s a fictional erotic story inspired by the typical themes of such narratives.

I've written an original version with a similar vibe — train journey, girlfriend's sister, tension, and escalating intimacy.

The train was unusually crowded for a mid-week AC 3-tier journey from Bangalore to Hyderabad. I had managed to get the side lower berth — 45 — and my girlfriend’s younger sister, Riya, had the middle berth right above me — 46.

My girlfriend (her di) was supposed to come with us, but last minute she got stuck with an office emergency and told me to “please take care of Riya” and drop her safely at her PG in Hyderabad. Riya was 20, just finished second year engineering, and had that dangerous mix of innocence and curiosity that makes older guys weak.

She climbed up to the middle berth wearing a loose pink kurti and black leggings. The moment she bent to keep her bag, the kurti rode up and I got a clear view of her smooth lower back and the thin black waistband of her panties peeking out. I immediately looked away… but not fast enough.

She caught me.

“Eyes up here, bhaiya,” she said in a teasing whisper, smirking as she settled on her berth.

I laughed it off. “Arre, window dekh raha tha.”

“Haan haan, window bilkul aapke samne hai,” she replied, rolling her eyes dramatically.

The train started moving around 8:30 pm. Lights were dimmed by 10. Most people were either sleeping or pretending to sleep with earphones in.

Riya kept tossing and turning above me. Every time she moved, her legs would dangle down a little from the middle berth, brushing my shoulder or arm. After the third time I finally whispered up,

“Thik se so ja, pair idhar udhar mat maar.”

She leaned down so her face was just inches above mine, hair falling like a curtain around us.

“Neend nahi aa rahi… bohot garmi hai,” she complained softly.

I could smell her shampoo — something fruity and sweet.

“Fan full kar du?” I asked.

“Already full hai,” she pouted. Then after a pause she added in a smaller voice, “Aur thoda adjust ho sakta hai kya… yaha niche?”

My brain short-circuited for a second.

“Middle berth pe adjust kaise?”

She bit her lip. “Nahi… aapke paas… side lower pe.”

My heart started hammering. The berth was narrow. Two people would be pressed together no matter what.

“Riya… log dekh lenge,” I said, trying to sound responsible.

“Sab so rahe hain. Aur curtain laga denge na,” she whispered. “Bas thodi der… garmi se maar rahi hu.”

I looked around. Curtains were mostly drawn. The uncle opposite us was snoring loudly. The family in the next coupe was dead silent.

Against every sane thought in my head, I shifted towards the wall and patted the tiny space beside me.

She climbed down quickly, smoothly sliding under the thin sheet I was using. The moment her body touched mine I realized how warm she actually was — and how soft.

She faced me, our faces barely 8 inches apart.

“Better hai ab?” I asked, voice hoarse.

“Thoda,” she murmured. Then her leg slowly came over my thigh like it was the most natural thing.

I froze.

Her knee brushed against my already hardening cock through the track pant. She didn’t move it away.

Instead she whispered, “Aap bhi to garam ho rahe ho…”

“Riya… yeh galat hai,” I managed to say, even as my hand instinctively went to her waist.

“To ruk jao na,” she challenged, eyes shining in the dim blue night light. “Ruk pa rahe ho kya?”

I didn’t answer. Instead my fingers slipped under her kurti, touching bare skin. She shivered.

Her hand moved down between us, boldly palming me over the fabric.

“Fuck…” I hissed under my breath.

“Shhh,” she giggled softly, then pressed her lips to mine — quick, testing.

I lost it.

Next second I was kissing her properly — deep, hungry, tongues sliding. Her nails dug into my shoulder while her other hand kept stroking me slowly, teasingly.

I pulled her kurti up. No bra. Just perfect small breasts with dark nipples already hard. I took one in my mouth and she gasped, immediately biting her own hand to keep quiet.

My fingers went inside her leggings. She was soaked. No panties either — just smooth, slippery heat.

She whimpered against my ear, “Finger daalo please…”

I slid one finger in, then two. She was tight, clenching around me instantly. Her hips started rocking in small movements.

Suddenly the train jerked hard at a station. We both froze.

Nobody woke up.

She looked at me with wild eyes and whispered, “Pant neeche karo… abhi.”

I pushed my track pant and boxers down just enough. My cock sprang free, painfully hard.

She turned her back to me, spooning position, lifted one leg slightly. I rubbed the head against her wet entrance once, twice… then pushed in slowly.

She buried her face in the pillow to muffle her moan.

It was hot, tight, slippery heaven.

I started moving — slow deep strokes at first, then faster. The berth creaked a little but the train noise covered it.

Her hand reached back, grabbing my ass, urging me harder.

“Jor se… please…” she breathed.

I covered her mouth with my palm and gave her what she wanted — hard, fast thrusts while my other hand pinched and rolled her nipple.

She came first — body shaking, thighs trembling, a long muffled cry against my hand. I felt her pulsing around me and that pushed me over.

I pulled out at the last second, spilling thick ropes across her lower back and ass under the sheet.

We stayed like that for a long minute — breathing heavily, sticky, hearts racing.

Then she turned her face, kissed me softly and whispered,

“Di ko mat batana… warna agli baar nahi milega.”

I could only nod, still dazed.

The train rattled on into the night.

And I knew this journey had changed everything.

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