Son Chaeyoung was a trainee from JYPE and she's Myoui Mina's hardcore fangirling or a known as Mina from the most lit girl group in 'K-Pop World' Twice. 

   After her debut as JYP's girl group called Thrice (i know but it's just a name right?) with 5 members all, (Jihyo, Dahyun, Tzuyu, Somi and her. So the rest were in Twice) they become closer day by day until Chaeng had a crush on Mina. 

   When the right time comes, she decided to confessed her feelings towards Mina eventhough she knew the risk that may affect her carrier nor Mina. Because of that, Chaeng make a deal. The painful deal. The deal that would hurts themselves. The deal was they must keep loving and missing each other till the end day of their story.