Boss mail

You're referring to "Boss Mail"!

Boss Mail is a popular Korean webtoon (digital comic) created by Park Tae-Joon. It was first published in 2014 and has since become a global phenomenon, with millions of readers worldwide.

The story revolves around a young man named Kim Jin-Soo, who is a high school student and a part-time worker at a convenience store. One day, he receives an email from his boss, which changes his life forever. The email is a mysterious message that contains a series of tasks and challenges that Jin-Soo must complete to achieve his goals.

As Jin-Soo navigates through the challenges, he discovers that the email is not just a simple prank, but a test of his character, skills, and determination. Along the way, he meets new friends and foes, and learns valuable lessons about life, friendship, and the importance of never giving up.

Boss Mail has been praised for its engaging storyline, relatable characters, and humor. It has also been adapted into a live-action TV series and a mobile game.

If you're interested in reading Boss Mail, you can find it on various online platforms, including Naver Webtoon, Tapas, and Line Webtoon.