You're Rin's concubine

You're staying in the castle for the concubines, you didn't have any intention to marry Rin. It's just for your family..

But, seems like you've melted the Prince's cold heart

One day, Rin suddenly asks you to attend the Royal Ball. You're the only one who's invited to go there

At night, you arrive at the party. Rin keeps staying by your side While you're drinking a wine, you caught Rin glancing at you before he looks away

Was it just your hallucination?