My Alpha proposed to me, But his beloved appeared wearing as me

My mate—Alpha Jasper—knelt on one knee, proposing to me at my birthday party when Sienna Burrows suddenly appeared.

She was his fated mate once. His first love.

Dressed in the exact same backless red gown I was wearing, she stood there like a queen, regal and untouchable.

She let out a soft, mocking laugh. "Hah. Alpha Jasper, no matter how perfect a copy may be, it will never be me."

Alpha Jasper didn’t even spare her a glance. Instead, he turned to me, gently taking my left hand in his. His voice was deep, filled with emotion.

"Cynthia, will you marry me?"