As a Villain, You Should Make Yourself Darker.

Mu Yan was tricked, and the person who tricked her was her own senior brother. From then on, she lived a life of carrying the system to different worlds to complete tasks. System: Main line mission released... Mu Yan: This task is simple. Isn't it just to make the villain black? Wait, I can complete it in three days. However... Three months later. Mu Yan looked at the 0% blackening value on the system, feeling very calm at this moment... Shit. Mu Yan: Villain, you should become darker! ! !