In her past life, she had interacted with all kinds of people - the cruel, the deranged, the weak, the benevolent... all types, and she had to manage various kinds of relationships with them, be they hostile, exploitative, collaborative, or friendly. She didn't have to specifically study how to deal with people, because life taught her that. She was good at exploiting people's weaknesses after all.
The ones who needed to be won over were moved by her sincerity and capability, whereas the potential enemies were increasingly resentful of her arrogance and shamelessness.
Consequently, the friendlier ones helped her more and more, and the hostile ones hated her more and more.
