I have been trying to find the manwha I was reading awhile ago, seems like it just disappeared. It was about a class of students, specifically Haegeum High School Students, class 5, that were invited to a game through their phones. Once the full class joined, they got a lot of money, and after each successful mission done, they would get more. The characters I can remember consist of a super rich dude and his team of bullies, a fit gym girl, and a hacker dude. Would thank anyone one hundred times if you could help me find it.

Sounds like Lustful Games