Sister, Don’T Mess With Me! summary:

“Warning: Mature content: This manga contains materials that might not be suitable to children under 17. By proceeding, you are confirming that you are 17 or older.”Wang Zhexing is someone who graduated from university recently. On his way to work, he was ambushed by numerous girls of unknown identity one after another. The assailants though, did not demand money from him. Apparently, their objective was to do something ( ͡° ͜ʖ ͡°) with him. Just when he could no longer hold off their “attacks” of throwing themselves at him, a girl named Mulian appeared. According to her, she came in order to stop other woman from robbing him of his virginity…… And that everything began from a single Task4Reward phone APP called “Handsome Reward”.