For the prom, the theme was 'Masquerade' and they had to hide their identity to make it more interesting. 

AUTHORS POV 

As Eun Mi went to put down the drinks, out of the corner of her eye, she saw someone wearing a tux and the Zorro mask. 

Sungjae. 

She smiled when she saw him. He looked charming. 

"Hey, babe!! Guess what I got the keys to my dad's car! He said he'll let me use his car just once hehe." Sungjae grinned and walked towards Eun Mi. He realised that Eun Mi was still in her work uniform.

"You're not going to the prom as a waitress are you?" He questioned her.

"Jae, I'm not going." Eun Mi said and then went to refill the coffee machine. 

"WHAT? What do you mean you're not going? What about the guy you're going to meet??" Sungjae asked while attempting to follow Eun Mi inside the workers range when Bong Cha shooed him out.

"The guy?" Bong Cha asked with a blank look on her face.

"Is he talking about the guy who has been sending you love notes?" asked Bong Cha.

"Bong Cha, they're not  love notes, they're emails," Eun Mi giggled.

"Eun Mi, if a man takes his time to write about his feelings for you, it's a love note." Bong Cha beamed.

"So you've got a secret admirer!!" Bong Cha grinned.

"And he wants to meet her, tonight at prom." Sungjae added and saw Eun Mi giving him a death glare.

"What are you still doing here?!" Bong Cha exclaimed.

"I'm obeying orders," Eun Mi said while refilling the napkins at the coffee counter.

"Babe, this is your true love!" Jae added.

"Well... true love is going to have to wait." Eun Mi walked away from them.

They followed her and Bong Cha said, "No, you are going to prom."

"I can't go. If Sung Ah finds out, she will kill me and then bring me back to clean up the restaurant." Annoyance raised in Eun Mi's tone.

"If she wants to hurt you, she's going to get through me." replied Bong Cha. 

"Eun Mi, your dad didn't leave this earth to see you unhappy, it's time for you to find your happiness, starting from prom." Bong Cha smiled. 

"Eun Mi, listen to Bong Cha, you're always studying, you're always working, you need to make time for yourself." Jae put his arm around Eun Mi. 

"I think you guys are right. I never do anything for myself. And I deserve to have some fun." Eun Mi said. 

"Yeah." Jae and Bong Cha said. 

"I'm going to prom, and I'm gonna dance with him all night." 

"That's my girl!" Jae hugged Eun Mi. 

Eun Mi was all smiles until she realised something. 

"Urgh, I can't go." Eun Mi bluntly said.

"What, why?!" Jae let go of his grip. 

"I don't have a costume." Eun Mi pouted.