CEO's Mistaken Lover

Cathy accidentally slept with her future boss Lester, and she is afraid of getting fired, so she disguises as a nobody and avoids contact with the boss. However, her boss mistakenly takes her sister Vivi for her. Things were going smoothly until their frequent interactions at work turned into something more, a lingering sense of familiarity, a breath-holding feeling of destiny, when would he realize it was her...?