The Professor's Pet-3

SOPHIA

My entire body locked up as Cain’s voice stayed perfectly calm on speakerphone. “Yes, Mom, Sophia’s right here with me. She’s making excellent progress on her thesis. Very dedicated.”

His thick cock was still buried deep inside my dripping pussy, throbbing against my walls. I was bent over his desk, skirt bunched around my waist, panties tangled at my knees, breasts smashed against the wood. Fresh slick from my last orgasm coated his shaft and dripped down my thighs. His fingers kept rubbing slow, torturous circles over my swollen clit, keeping me right on the razor’s edge.

I bit my lip so hard I tasted blood, fighting the moan that wanted to rip out of me.

Cain rolled his hips in a deep, grinding thrust that made his cock drag perfectly against my g-spot. My eyes fluttered shut. *Oh god, this is so wrong.*

“Tell her how hard you’re working, little sister,” he murmured, voice low enough for only me to hear, while his free hand squeezed my ass cheek hard.

I forced my voice steady, shaky but audible. “H-hi Mom… yeah, Cain’s helping me a lot. I’m… I’m really pushing myself right now.”

Mom’s warm voice filled the office. “That’s wonderful, honey! I knew having your stepbrother as your advisor would be perfect. You two have gotten so close since the wedding.”

Cain chuckled softly, the sound vibrating through his chest against my back. He pulled almost all the way out, then slammed back in with one brutal stroke. The wet slap of skin on skin was faint but unmistakable to my ears. I clenched hard around him, my pussy fluttering wildly.

“Yes,” he said smoothly to Mom. “We’ve become very close. Sophia’s learning to take everything I give her.”

His fingers sped up on my clit. He fucked me in short, powerful thrusts—deep enough to make my toes curl, quiet enough not to alert Mom. Each stroke stretched my soaked walls, his heavy balls tapping against me. The obscene squelching sounds of my cunt taking his cock filled my ears. I was going to come again. With my own mother listening.

“Cain… please…” I whispered desperately, barely a breath.

He pinched my clit lightly in warning and thrust harder, angling to hit that perfect spot over and over. Pleasure coiled tight in my belly, hot and terrifying.

Mom kept chatting happily about family dinner next weekend. “You should both come over. It’ll be nice to have my two favorite kids together.”

The guilt hit me like a wave, but it only made my pussy clench tighter around him. *This is sick. He’s my stepbrother. Her stepson.* Yet my hips rocked back to meet his thrusts, chasing the pleasure only he could give me.

Cain’s breath was hot against my ear. “You’re such a filthy little secret, aren’t you? Coming on your stepbrother’s cock while Mommy talks about family bonding.”

He slammed into me faster, still somehow keeping the rhythm controlled. His cock swelled inside me, stretching me even more. The dual sensation of his thick length pounding my pussy and his expert fingers on my clit pushed me over.

I came violently.

My walls spasmed and squeezed around him like a vice. A choked whimper escaped despite my efforts. Fresh juices gushed around his cock, soaking his balls and dripping onto the floor. My thighs shook uncontrollably. Stars burst behind my eyes as wave after wave of shattering pleasure ripped through me.

Cain kept fucking me through it, slow and deep, prolonging the torture. His cock throbbed inside my convulsing pussy.

“Sounds like you’re working hard, Sophia,” Mom said cheerfully. “I’m so proud of you.”

Cain’s voice was perfectly normal. “She’s taking it *deep*, Mom. Really committing.”

The moment Mom said goodbye and the call ended, Cain pulled out of me, spun me around, and lifted me onto the desk facing him. He shoved my legs wide apart, hooking them over his elbows, and drove back inside me in one savage thrust.

“Fuck, Sophia,” he growled, finally letting his control slip. “You’re so fucking tight when you come like that.”

He fucked me with raw power now. The desk banged against the wall with each brutal snap of his hips. My breasts bounced wildly. He leaned down and sucked hard on one nipple, then the other, biting just enough to make me cry out.

I wrapped my arms around his neck, lost in the overwhelming sensation. His cock pistoned in and out of my soaked cunt, hitting deep with every stroke. The wet, filthy sounds of our fucking filled the office.

“You’re mine,” he snarled between thrusts. “Say it.”

“I’m yours,” I gasped, tears of overwhelming pleasure leaking from my eyes. “My pussy belongs to my stepbrother. Please… don’t stop.”

He reached between us and rubbed my clit again. Another orgasm crashed over me almost immediately. I screamed his name, my walls milking him desperately. Cain groaned, his rhythm faltering as he chased his own release.

But he didn’t come inside me.

Instead, he pulled out at the last second, fisted his glistening cock, and painted thick ropes of hot cum across my breasts and stomach. The sight of his seed marking my skin sent another shiver through me.

He stepped back, admiring his work—my flushed, naked body spread on his desk, covered in his cum, pussy still twitching and leaking.

“Clean yourself up,” he ordered, voice dark. “You have a new deadline. Tomorrow night. My cabin. If you fail again…”

He picked up my phone from the desk and showed me the screen. He had opened my email draft to the department chair.

A single sentence was typed: *I’ve been having an inappropriate relationship with Professor Hilton.*

My blood ran cold.

Cain smiled cruelly. “One click, little sister, and your entire academic career is over. Now get dressed. And don’t even think about washing my cum off before you leave campus.”

He tossed my blouse at me, cum still dripping down my tits.

As I shakily buttoned it over the mess, my mind raced with panic and twisted desire. How much deeper could this go before it all exploded?

But the worst part? I already knew I’d show up at his cabin tomorrow night.

What twisted new “tutorial” does Cain have planned for me at the remote cabin? Will I finally break and beg to be his full-time submissive… or will a shocking discovery there change everything between us forever?