Season 1

The two people who have to keep meeting each other at work even after a complete breakup have a hard time. But a few days later, Yoon-seo starts receiving mysterious 'text messages from unknown senders'.

Joo-won responds to Yoon-seo's feelings of confessing her feelings while being swept up in the atmosphere, and makes a public confession. The next day, when the two meet at work, they are left with dizzying memories.

Now, as the AL CARD's director and Yoon Seo's superior, Ju Won declares war against Yoon Seo in an office he picked right next to hers. He vows he will never let her go and turns up his charms. He attacks her by flirting and clings to her in the most pitiful way. Meanwhile, Yoon Seo succumbs to his request to eat with him 27 times.

After dating Ju Won for a year and a half without knowing he was the youngest son of the AL Group family, Yoon Seo decides to break up with him at his mother's request while accepting her money. As promised, she attempts to break up with him by making him gradually resent her. However, she gets drunk and unknowingly calls him to break up.