Sinful Obsession: My Billionaire Stepbrother

Bonding With Work

I clocked into Sterling Global at 7:30 AM, my footsteps echoing through the hollow, marble lobby.

The only other people around were the maintenance crew, and I’m pretty sure the guy buffing the floors thought I was crazy for being there voluntarily on a Saturday.

If it wasn't for my scheming stepbrother and the impossible deadline I’d accidentally handed the press, I would be at home right now, probably in a long bath or prepping my skin for the freshman party.

Instead, I was here, fueled by black coffee and a desperate need to prove I wasn't the charity case William thought I was.

I had purposely left the mansion an hour early, taking a cab just to avoid giving him the satisfaction of driving me. I wanted to be already buried in work by the time he arrived, a silent statement of my dedication.

But when he finally appeared at 8:30 AM, I found it hard to stay annoyed.

He was dressed casually dark, well-fitted jeans and a designer tee that looked soft enough to touch. He looked dashing as always, but there was something about the relaxed attire that made him seem even more breathtaking. It stripped away the corporate armor he was used to wearing on weekdays and left just the man, a beautiful normal man.

"You're here," William noted, walking toward his office.

"You didn't wait for me to give you a ride."

"I wanted to check in and prepare mentally," I replied, keeping my eyes on my laptop screen.

I was still a little mad that he’d used my pride to drag me into the office on a weekend, but I knew I had to be responsible for the three-month promise I’d made.

We went into his office, but before he opened a single file, he reached into a bag and pulled out a spread of breakfast sandwiches and fruit then handed them to me.

"Breakfast first before work," he simply said.

I looked at the food, then at him.

It was incredibly thoughtful I must admit, especially since I’d skipped breakfast in my rush to out-work him.

"Thanks," I murmured, the anger in my chest softening just a fraction.

We dove into the work immediately. It was a mountain of permits, environmental impact reports, and contracts that needed signing.

We spent hours discussing the logistics, making impromptu calls to project managers, and highlighting sections that needed legal review, despite the tension between us, we worked well together. We made a great team together.

At noon, we were only halfway through the first stack.

William stood up to take a call, pacing toward the massive floor-to-ceiling windows that looked out over the London skyline. I took a moment to breathe, but my eyes betrayed me.

They somehow made their way to his figure, I found myself admiring his stature, those broad line of his shoulders, the way he stood with such effortless power.

‘He’s your stepbrother, Isabel! Stop this!’ I mentally yelled at myself, practically wanting to slap my own face. It was wrong to notice how well his jeans fit or how his hair looked slightly messy and perfect.

After his call, a man arrived for a brief meeting. They spoke in hushed, serious tones in the corner of the office. I tried to pay attention to my ledgers, but I felt William’s eyes on me several times. When the man finally left, William returned with lunch—hamburger and sparkling water.

"So, about this party," he asked as we took a break to eat. "Are you still going? Won't you be too tired after all this?"

"I’m going to try to meet up with them," I said, looking at him with pleading eyes. I felt a sudden wave of exhaustion hitting me.

"My social life is basically zero since I moved here, William. I need to chill out a little or I might get old with stress.

Would you really like your stepsister suddenly showing up with grey hair and wrinkles?"

I pouted at him, a bit of my natural sass leaking through the professional fatigue.

To my surprise, William didn't roll his eyes or make a snarky comment, Instead, he laughed.

It wasn't a cold, mocking chuckle. It was a real, genuine laugh that reached his eyes and made his whole face transform.

I froze, halfway between mouthfuls.

I had never seen him truly laugh before. He looked... beautiful.

"You’d still be as beautiful as ever, Bel," he said softly, his voice dropping to that cold edge I knew him for.

Suddenly, the air in the office felt thick and hot.

The playfulness vanished, replaced by that heavy, magnetic tension that always seemed to find us when we were alone.

My heart hammered against my ribs, and for a second, I thought he might walk across the room and bridge the gap between us.

I sat upright and cleared my throat, desperately trying to break the spell. "Let's... let's just focus on work. We still have the garage section to overlook."

"Right," he said, but his eyes lingered on me for a second longer before he nodded toward the desk.

"Finish those files and we can go. It’s already 5:00 PM."

We finally finished at 8:00 PM.

My eyes were burning and my fingers felt cramped from signing so many documents, but the Greenfield Project finally felt under control.

We cleared the table in a tired silence and headed down to the car.

The drive back to the mansion was quiet,I enjoyed the solitude with the city lights blurring past the windows.

As the black Bentley pulled up to the massive iron gates, I noticed a car idling just outside. A girl was standing by the gate, pacing back and forth and looking at her watch.

Chloe!

She was dressed in a shimmering silver mini-dress, her hair done in high, bouncy pigtails. She looked ready to tear the roof off the party building.

Just as William steered the car through the gates, my phone began to vibrate in my lap. It was her.

I looked at the gate, then at William’s profile in the dim light of the dashboard. My Saturday of responsibility was officially over, but looking at my best friend waiting for me, I realized the night was only just beginning but I was already exhausted.