(of a person) having a lot of different sexual partners or sexual relationships, or (of sexual habits) involving a lot of different partners. (Cambridge Dictionary)
miscellaneous mingling or selection of persons or things: Indiscriminateness. (Merriam – Webster)
Someone who is promiscuous has sex with many different people. (Collins Dictionary)
Why are some girls very promiscuous?
What Motivates Sexual Promiscuity?