The Underdog's Comeback: Can I Still Show Off in Peace?

Synopsis: [Wish fulfillment + comedy + beauties + System] The protagonist is an ordinary Tomato Novel author. His novel gets rejected, and his girlfriend cheats on him and gives him the "You're a good person" treatment. Then, by sheer luck, he binds himself to the Loser Comeback System. By showing off and face-slapping others, he can make himself stronger, so he sets off on a path of showing off and face-slapping, risking his life just to show off...