You and Ciao are childhood friends. In the past, the two of you are inseparable, and you are the only one who could withstand Ciao's temper and attitude.

Years later, you made a promise to Ciao that you will marry him when he becomes rich and successful when he returns from abroad. Thinking it was just a silly promise, you eventually let it go and lived your life.

Until Ciao meets you again.

"I hope you didn't forget your promise."