Epstein was running an elite favor trading network. You wanted to rape a teenager? Epstein can arrange that, but now you owe Epstein a favor. You need a favor from someone? Epstein can arrange that, but now you owe Epstein a favor for someone else.

Sometimes, favors are traded in for cash. I.e., if you're a billionaire and you let Epstein be a financial advisor managing $1B, and he charges 2% a year management fee, now you're giving Epstein $20M per year.