Chapter 1

During her first-birthday selection ceremony, Seraphina held tightly onto the hands of her two childhood sweethearts from the Vanderbilt family.

The elder of the two was the older brother, Christian, who was courteous, refined, and gentle.

The younger was the brother, Caspian, who was wild, rebellious, and fiercely clear about his loves and hates.

The two of them fought tooth and nail over her, engaging in intense rivalry for eighteen long years.

In the end, Seraphina chose Christian to be her husband.

Yet, on a night of burning, breathless passion, Christian leaned against her neck and murmured in a low, husky voice, "Sister-in-law."

...

That single call of "Sister-in-law" left Seraphina’s mind in utter chaos.

Looking at Christian, who had already pulled away and got out of bed, she grabbed his arm without a second thought and asked in a trembling voice.

"Who on earth are you? Are you Chris or Cas..."

Christian turned his head. On his deep, sharply chiseled face, aside from a lingering trace of post-passion desire, there was nothing but tenderness.

"Sera, even if Cas is my own brother, I still get jealous when you think of him so often."

With that, he got up and walked into the bathroom.

The sound of rustling running water drifted out, pulling Seraphina’s thoughts back into the past.

The top-tier old-money family, the Vanderbilts, had two young masters: Christian and Caspian.

They were identical twins, sharing the exact same face, yet their personalities were polar opposites.

Christian possessed an unblemished character and was established as the family heir at the age of nineteen, becoming the gold standard for every gentleman in high society.

Caspian, however, was recklessly arrogant, a man who sought vengeance for the slightest grievance since childhood, widely rumored to be the incarnation of chaos itself.

The two brothers had competed secretly for Seraphina, waging a masculine war that lasted over a decade.

When watching movies, if Christian fed her popcorn, Caspian would deliberately knock over the popcorn bucket;

At dinner, if Christian cut her steak, Caspian would hide her knife and fork.

She had never liked the obsessive Caspian, so when they grew up, she accepted Christian’s confession.

But Caspian refused to accept it, madly abducting her to Iceland and keeping her confined for a month, treating her as his exclusive possession.

When Christian found out, he taught Caspian a lesson for her sake, and during their violent brawl, Caspian fell into the ocean and vanished without a trace.

This incident left an indelible psychological trauma on Seraphina.

With a soft click, the bathroom door opened, releasing a cloud of warm steam.

Christian stepped out, fully dressed.

"Sera, everyone is still waiting downstairs to celebrate my birthday. I’ll go down to host them first, you sleep a bit longer."

As he spoke, he leaned down and pressed a gentle kiss to her forehead.

The familiar kiss soothed the sudden panic rising in Seraphina’s heart.

After Christian left, she also tried to dispel her emotions, getting out of bed to freshen up before heading downstairs.

From a distance, Seraphina spotted Christian in the living room, laughing and talking with several close friends.

A smile bloomed on her lips, but as she walked toward them, she was frozen by a voice.

"Cas, you really put your sister-in-law through the wringer just now. The boys thought you wouldn't make it downstairs tonight."

"If you ask me, you're the one who can really act, Cas. Putting on your brother’s face to sleep with your sister-in-law for three whole years."

"Back then she didn't choose you, and she wouldn't even look at you no matter how much you begged. Now, isn't she just taking her pleasure beneath you every single night, letting you play with her in every imaginable way."

The disgusting, mocking laughter made Seraphina freeze in her tracks, her mind feeling as though it had exploded.

What was going on? How did Christian become Caspian?

She stared at the suited figure beneath the lights. That slightly tilted chin, carrying a trace of careless defiance, gradually merged with the Caspian in her memory.

Could it be that for the past three years, the person staying with her day and night was actually Caspian?!

Before she could make sense of it, the front door was pulled open.

Seraphina followed the sound and saw a tall, upright figure walking inside.

The man wore a custom black suit, his aura noble and refined, possessing a deep, sharply chiseled face that was identical to Caspian’s at the center of the room.

The only difference was the golden brooch pinned to his lapel, symbolizing the identity of the Vanderbilt family head!

This was the real Christian.

At this moment, Seraphina couldn't stop shivering, her fingernails digging so deeply into her palms that they nearly drew blood.

Christian walked straight toward Caspian, his gentle voice carrying an unquestionable authority.

"Cas, don't take it too far. I only allowed you to stay by Sera’s side using my identity, I didn't tell you to hurt her."

Caspian raised an eyebrow, a mocking sneer curving the corner of his lips.

"Brother, you were the one who said you only saw Seraphina as a sister, and that you wanted to pursue your little secretary. That’s why we planned this little switch, letting me fulfill your 'husbandly duties' for you."

"If you regret it, we can switch back. But don't forget the old man’s orders—he wants a grandchild this year. If you don't find her dirty, go ahead and sleep with her."

Christian didn't reply, but his gentle brow furrowed slightly.

His unspoken disgust was like a bucket of ice water, completely extinguishing the last remaining shred of illusion in Seraphina’s heart.

Chapter 2

The distant sounds of laughter and joy continued, but Seraphina returned to her room alone.

She sat in front of the vanity mirror, which reflected her deathly pale face.

In the next second, she opened the drawer and pulled out a signed divorce decree from the innermost layer.

This was something Christian had signed and given to her himself when they first married.

"Sera, this is my first time being a husband, so this is my guarantee to you. In the future, if I ever do poorly or make you feel wronged, you can take this out at any time to punish me."

Back then, Seraphina didn't understand why the "guarantee" Christian gave her was a divorce decree.

He had treated her with gentle care since childhood, treasuring her above all else.

Every time Caspian provoked her, Christian would stand in front of her to protect her.

Even after she was rescued from Caspian’s kidnapping, when everyone said she had lost her purity and was no longer worthy of him, he still accompanied her to see a psychologist. He even ignored all the malicious rumors to give her a grand wedding that shook high society.

She had genuinely believed that he loved her.

It wasn't until today that she completely understood.

Christian only ever saw her as a sister, which was why he had prepared the divorce decree so early, leaving her an escape route.

A dense, bitter ache flared up in her chest once more, like being repeatedly pierced by fine needles.

Suppressing her emotions, Seraphina hesitated no longer, picking up a pen to sign her name on the agreement.

Christian did not love her, and he had even gone so far as to swap identities with Caspian to deceive her.

Then there was absolutely no reason for this marriage to exist.

Putting the agreement away safely, Seraphina intended to rush to the family court.

Just then, the bedroom door was softly knocked.

In the next second, the real Christian pushed the door open and walked in, asking her softly.

"Sera, have you rested enough?"

Seraphina calmly hid the agreement, then looked at him, forcing a faint smile. "Yes."

Christian naturally extended his hand to her.

"Then let's go downstairs. I still have a surprise for you."

The two arrived in the living room, where the birthday party was still underway.

Standing beside Caspian was a woman dressed in a pink gown, her face bright with a beaming smile.

As they drew near, Christian’s gentle voice sounded beside Seraphina’s ear at just the right moment.

"Sera, Cas didn't die. He just came back today. He wants to apologize to you in person for the kidnapping back then."

As soon as the words fell, Caspian looked up at Seraphina, a careless, rebellious smile playing on his face.

"Sister-in-law, it was my youth and possessiveness at work back then that caused me to offend you. I apologize."

With that, he leaned over to wrap an arm around the woman's waist beside him, his tone becoming intimate.

"Let me introduce you. Natalia, my girlfriend. She was the one who saved me after I fell into the sea back then. These past few years, she’s completely tamed my rebellious streak. I’ve met my match."

Immediately following, Natalia also echoed with a smile, "Mrs. Vanderbilt, long time no see. I never expected we would end up as sisters-in-law."