TV版N O#039PENing One Reason Why We Cannot Meet

Won Young and Ki Joon met at a random birthday party for the first time. The two somehow ended up spending the night together, but went separate ways the next morning without turning back. However, they both didn't realize that birthdays happen every year. A year later, they meet again and start spending more nights together. Then suddenly, Won Young proposes to live with Ki Joon.