He did what Keith Rainiere did. They attach themselves to large piles of money by cozying up with rich people, then create a situation where their victims have no choice but to go along with whatever scheme they have. It starts with charisma and being an old-fashioned conman, but then it morphs into something much more dark. By creating an air of legitimacy around themselves, people are under the impression they can be trusted with large sums of money. An insider tip here, a flight with a 17 year old, there... and it slowly escalates. A lot of figures in history are really good examples of how this works. Joseph Smith Jr, who founded the Mormon church is one of the most interesting charismatic figures in history. He started his own bank and started printing money like there was no tomorrow and essentially running off with everyone's investments. In the case of NXIVM, a harem of successful women would attract other women and they wouldn't meet Keith Rainiere until after his reputation had been built up as "smartest man in the world." Girls' night out would eventually involve some naked pictures, classes were for 20k a piece, but, don't worry, we'll lend you the money... then you have these women who have naked pictures of themselves, owing more than they can ever repay and they are slowly escalated into being criminals themselves.