My Revenge with The Underworld Mafia

Kourtney P. O. V

Ever since I moved in my step-sister's house, I found myself drawn to her husband, Matthew. I knew it was wrong to fall for my brother-in-law, but I couldn't help myself.

Who wouldn't be captivated by a man like Matthew, who seemed to have it all? Wealth, intelligence, and, above all, undeniable charm.

Matthew was kind to me, treating me like a younger sister, but I craved more than that. I wanted him to see me as a grown woman. After all, I was at the right age where I could do whatever I pleased.

"Kourtney, I'm heading out for a bit," I heard Matthew say.

"Where are you going?" I was surprised to see him in a suit, looking even more handsome than usual.

"It's our wedding anniversary tonight, so we're celebrating," he replied with a smile.

I forced a smile back, but deep inside, a pang of envy stabbed at my heart. I'd long been envious of Lorelei, for she was the one Mathew loved.

I had tried, countless times, to tempt Matthew, to win his heart, but it was Lorelei he truly desired.

"That's good to hear, Matthew, but wait, I have something for you!" I blurted out, a plan forming in my mind.

I would disrupt their date, shatter their relationship. I didn't care if it hurt Lorelei, we weren't truly sisters.

"What is it?" Matthew asked, intrigued.

I grabbed a shake from the kitchen, a concoction laced with a medicine that would induce hypersexuality.

"I made this shake, and I want you to try it. I want to know if it's good or not," I said, handing it to him.

Matthew was surprised, but he took a sip, "Wow! This is delicious. You're doing great, sweetie."

"Aww! Then finish it," I urged, a wicked grin spreading across my face.

I watched with satisfaction as he drained the shake, the effects of the medicine starting to take hold.

"Wait, I'm getting dizzy," Matthew groaned, clutching his head. He swayed, about to fall, and I caught him, guiding him towards the bedroom.

"It's alright, Matthew. You'll be fine," I said, though my heart hammered in my chest.

Once inside, I began my mission. I sat on top of him, my fingers working to undo his buttons.

"Kourtney, what are you doing?" His voice was weak.

"Matthew, I want to make love with you," I whispered, my breath hot against his ear.

"No, Kourtney. This is wrong," he protested, trying to push me away. But I silenced him with a kiss, claiming his lips.

I held him, kissing him deeply, until I felt his response, a tremor of desire running through him.

Suddenly, I was naked, Matthew on top of me, his hips thrusting against mine. I felt his length inside me, a sharp, tearing sensation. A delicious pain, a primal ache that made me moan and grip the sheets.

"Faster!" I cried out, my voice ragged with need.

Then, a wave of heat exploded inside me, lifting me to a dizzying peak. I squeezed my eyes shut, savoring the moment, a memory forever etched in my mind.

"I love you, Lorelei," he whispered, his voice thick with emotion. I stared at him, my heart sinking.

I thought in this moment, in this shared intimacy, he would forget Lorelei. But her name still clung to his lips, a constant reminder of her presence in his heart.

***

"Kourtney, what happened last night?" Matthew asked. He couldn't remember the night before, and the missed anniversary date weighed heavily on him.

I lowered my gaze, pretending ignorance. "I-I don't know. I just found myself beside you."

Matthew's eyes widened, a flicker of realization crossing his face. "No way! Tell me nothing happened between us last night?" His voice was sharp, tinged with anger.

"I'm not sure, but I think we did it," I said, biting my lip, trying to appear innocent.

Matthew jumped out of bed, scrambling to get dressed. "This is crazy! We can't do this, Kourtney. You know I'm married, and I love your sister so much!"

"I know, but she doesn't love you the way I do. Matthew, why don't you just divorce her? Marry me instead. I can give you everything you want," I pleaded.

"Shut up! You're out of your mind. Lorelei would never forgive me if she found out. " Matthew snapped, turning to leave. But I stopped him.

"Matthew, please. Why don't you try to love me? I'm always here for you." I cried, trying to change his mind.

Matthew turned back, his gaze sharp and cold. "Kourtney, I'm making this clear. I don't feel anything for you. I only see you as a sister. And Lorelei is the love of my life," he stated firmly.

Tears streamed down my face as his words pierced my heart. It was excruciating, the pain of unrequited love.

***

Days passed, and I noticed Lorelei hadn't returned home. I had no clue where she was. Matthew avoided me, consumed by his search for her. She had been missing for three days.

But one day, Lorelei suddenly went back home. Mathew and I were both taken aback.

"Lorelei? Where have you been?" Matthew asked, as he tried pulled her into a tight embrace.

"I'm sorry I didn't inform you guys, I'm taking a vacation alone." she replied, offering a small smile.

My heart pounded as I met Lorelei's gaze. It was chilling, a look that sent shivers down my spine.

"Kourtney, Matthew, I have a surprise for the both of you." Lorelei said, handing me an envelope.

I opened it, and both Matthew and I gasped.

Inside, we found a divorce agreement paper.