Chapter 1

I returned from my business trip to find a new lock installed on the master bedroom door.

My fiancé, Ethan, was hunched over his phone, browsing furniture.

"Serena’s new rental place is awful. I offered her our master bedroom for now."

"Here’s an IOU."

He casually pulled a crumpled piece of paper from his pocket, scribbled with both of their names.

Another IOU.

Six months ago, his college mentee, Serena, borrowed my designer coat. The very next day, photos of her and Ethan in matching outfits went viral on our company Slack, while rumors painted me as the bitter third wheel.

A year ago, after months of planning our dream vacation, I got to the airport gate only to find my ticket was missing.

Ethan had given my first-class seat to Serena, claiming she’d never been out of the country before.

At the boarding gate, he had smiled, handing me an IOU note.

Then he turned around and walked away without looking back once.

I had accumulated twenty-six of these crumpled notes.

I had smoothed and folded every single one, keeping them locked in an old tin box.

Now, Ethan watched as I pulled that tin box out of my bag. He expected me to do what I always did—swallow my pride and accept it.

Instead, I set the box gently on the coffee table.

Along with my engagement ring.

"Don't bother paying me back."

"You can keep the apartment. And you can keep yourself."

Ethan finally looked up.

His eyes clouded with irritation.

"Serena is my junior. It’s my job to take care of her."

He stood up slowly.

He took my hand, trying to slide the diamond ring back onto my finger.

"It’s just a bedroom, Anna."

Just?

A bitter laugh escaped my lips.

Ever since we met her, Ethan had always found ways to favor this mentee of his.

Five years ago, his startup suffered a massive funding crisis and stood on the brink of bankruptcy.

I poured all my savings into his company without a second thought.

I even sold my luxury bags and jewelry to keep him afloat.

Yet the very next day, he loaned all that cash to Serena.

"She got into grad school. I couldn’t bear to see financial troubles rob her of such a great opportunity."

"Consider it a loan from me to you."

That was the first IOU I ever received.

It seemed that in their twisted minds, scribbling an IOU made every unforgivable betrayal completely reasonable.

When I was hospitalized after a car crash, Serena tossed another IOU at me.

"Anna, my family is pressuring me to bring home a successful boyfriend. I’m borrowing Ethan to show off for a bit."

They disappeared together for three whole months.

From the moment of the crash to the day I was discharged, Ethan didn't call me once.

Note after note, suffocating the life out of me.

I ignored Ethan entirely.

I unlocked my phone, staring at an unread email draft.

A week ago, I received an official offer from a premier luxury jewelry design house in Europe.

It had been my dream studio for years.

Yet I had hesitated.

I had put my future with Ethan ahead of my own career.

Clearly, I had never been his priority.

Without another second of hesitation, I typed my reply:

I accept the offer. I will report on schedule.

The moment the confirmation screen flashed, an overwhelming weight lifted off my chest.

I grabbed my suitcase handle.

Just as I opened my mouth to tell him it was over, the doorbell rang.

Serena strolled in, surrounded by a crowd of mutual friends.

"Congratulations on the new penthouse, Ethan!"

Confetti cannons went off with a loud pop.

Colorful ribbons drifted down, showering Ethan and Serena, who stood together right in the center of the living room.

Suddenly, I noticed the gourmet dinner on the dining table wasn't set for me.

A housewarming party. And I was the last to know.

The group naturally moved on to unwrapping gifts.

Ethan’s childhood friend, Mark, held up a high-end designer oven.

"Serena said she wanted to get into French baking, so I picked this out especially for her!"

Ethan’s college buddy hauled in an ergonomic luxury desk chair.

"Serena spends hours doing academic research. This custom chair is designed for long hours."

Chloe pushed through the crowd with an amused grin.

"Wait, isn’t this Ethan’s place? Why are all the gifts for Serena?"

She winked and popped open an elegant box.

Inside was a set of silk pajamas.

"You need great sleepwear to rest well."

"It's a matching couple’s set, by the way..."

Chloe’s voice trailed off.

Everyone suddenly seemed to remember I was standing right there. Awkward, guilty glances shot toward me.

"Anna, I didn't know your size, so I didn't grab a pair for you," Chloe stammered.

"Why don't you pick a set online right now?"

Out of the corner of my eye, I saw Serena duck her head, hiding a smug smirk.

"So, I'm the last person to know Serena is moving into my new home?"

I emphasized every single word.

I was the one who researched every neighborhood to find this location.

I pulled all-nighters for an entire month drafting the interior design blueprints.

I visited every single furniture showroom in the city, rushing over between grueling shifts just to supervise the contractors.

This was the home into which I had poured my entire heart and soul.

And yet, I was the last one told.

The room dropped into absolute, deafening silence.

I looked around at their faces—embarrassed, defensive, but not a single shred of real remorse.

Ethan’s buddy broke the silence first.

"Come on, Anna. Don't be so petty."

Chloe chimed in, annoyed.

"We did this for your own good. If we told you earlier, you would’ve thrown a massive tantrum."

Right. Of course I would have.

Because of Serena, Ethan and I had fought countless times.

He always claimed she was just a little sister to him, that he harbored no inappropriate feelings.

Yet when I demanded he cut contact, he refused.

When I demanded he stop lending her our things, he refused.

Ethan insisted that whatever he gave Serena was merely superficial, while his true heart belonged to me.

Yet right now, as I stood alone against the entire room, Ethan took a quiet step forward.

He shielded Serena behind his back.

His heart had belonged to someone else all along.