Sinful Obsession: My Billionaire Stepbrother

It Was A Mistake

It was strange; I’d spent so much time wishing William would just leave me alone, but once he actually became a ghost in the house, the silence became deafening.

I didn't see him at breakfast, his chair was empty at dinner, and the heavy oak door to his study remained firmly shut.

Part of me wondered if he was avoiding me because of the kiss—or if he was just done with me entirely.

By Friday, I couldn't take the walls of the house anymore. I headed into the office, my mind set on one thing: my future. If I was going to survive this internship, and I needed to be in the legal department

When I arrived at the Sterling Global headquarters, the glass tower felt even more intimidating than usual.

I checked my reflection in the lobby mirrors, adjusting the lapels of my blazer. Today wasn't just about filing papers; I was going to ask for what is practical to my field of study.

When I stepped off the elevator on the fiftieth floor, I ran into Jax. He was leaning against a desk, nursing a coffee, and his face lit up when he saw me.

"Look who decided to grace us with her presence," Jax teased, offering a friendly smile. "Where have you been hiding, Mayfield? The office has been way too serious all week."

"Busy with school," I explained, leaning against the counter beside him. "The workload is piling up, so I’ve had to scale back. I’ll mostly be coming in on my free days and Fridays for now."

Jax nodded understandingly. "Well, we’ve missed you. Sophia has been in a mood, and without you here to soak up her glares, she’s been spreading joy to the rest of us."

I laughed, though the mention of Sophia made my stomach tighten.

"Actually, Jax, I wanted to ask you something. As a law student, and as much as I appreciate learning the ropes here, I want to be where the real action is. Do you think there’s a chance I could move to the legal department?"

Jax took a slow sip of his coffee, his expression turning thoughtful. "The legal department is a bit of a huge deal, but the timing might be on your side. I heard a rumor through that the company is going to be merging with Vance Law for a few months.

“They’re bringing them in as legal aid for a massive acquisition. If you want in, now is the time to make a move."

My heart took a little leap. Vance Law was one of the top firms in the city. If I could even just shadow their team, it would be a game-changer for my career.

"You should talk to William," Jax added, nudging me. "He’s the only one who can sign off on a transfer like that. He’s in his office, but he’s been in back-to-back meetings all morning. Good luck, Izy."

I thanked him and headed toward the corner office, my palms starting to sweat. This was it.

I reached the heavy glass doors just as they swung open. Three men in sharp, expensive suits walked out, deep in conversation. They politely nodded at me as they passed.

William was standing behind his desk, his back to the door, staring out at the London skyline.

Even from the back, he looked commanding. The tension in his shoulders was visible through his navy suit jacket.

"William?" I said softly, standing in the doorway.

"Do you have a few minutes? I’d like to discuss something with you."

“Sure come in” he gestured with his hands to the seats

His expression was the same mask of cold indifference he’d worn since the day we met, but his eyes... they were darker than usual. There was a flicker of something dark and hot there—like could see my soul and my thoughts

I walked into the office, the click of my heels on the hardwood floor sounding like gunshots in the quiet office. I didn't bother to sit.

I stood by the chair, gripping the back of it for support.

"I wanted to talk to you about my role here. I’m a law student, and I feel my skills would be better utilized in the legal department, so I’d like to transfer."

I waited for the bite. I waited for him to tell me I was unqualified or that I should be grateful to even have a desk. But it didn't come.

William leaned back against his desk, his arms folded across his chest. He looked at me.

"The legal department," he repeated quietly. He didn't scoff. He didn't even argue. "I’ll consider it, Isabel. It’s a big move, but you’ve proven you can handle the pressure."

I blinked, completely caught off guard.

Where was the bickering?

Where was the Ice Prince who lived to make my life miserable?

He was being... calm. Understanding. It was almost weirder than him being mean. Was he being nice because of what happened between us?

The silence stretched, turning heavy and thick with the one thing I was trying to ignore. The memory of the kiss suddenly felt like it was playing on a loop in the office.

"About the other night..." I started, the words tumbling out before I could stop them. I felt the heat rise in my cheeks, a deep blush staining my skin. "It was a mistake. I think... I think we should just not talk about it. It’s in the past. We’re step-siblings, William. It shouldn't have happened."

I looked at him, searching for a reaction. For a split second, something flickered in his whiskey-colored eyes something sharp and dark but his face remained a mask of perfect composure.

"I see," he said. His voice was flat, unreadable.

He went to say something else, his lips parting as he took a step toward me, but I didn't give him the chance. My survival instincts kicked into high gear.

"I should get back to work. Thanks for considering the transfer," I said breathlessly.

I turned on my heel and practically bolted for the door. My heart was hammering against my ribs so hard it hurt.

As the glass door clicked shut behind me, I let out a breath I didn't know I was holding. He was being nice. He was being reasonable. And for some reason, that made him ten times more dangerous than he had ever been before.

I headed to my desk, my mind a total wreck. I just hoped this new, calm William would last, because if he kept looking at me like that, I was never going to make it through the weekend—let alone the semester without my attraction to him growing into something deeper.