i'm thinking someone he became close to and/or hooked up with over the last couple of years; he trusts them a lot, and while initially throwing his family's money around was a way to impress them* it's since become an unspoken thing where he just buys everything when they're together and has helped them with rent or other big issues. i imagine his family having a lot of associates throughout different industries so some of it might be a little shady, like him getting his pseudo uncle who works as a car salesman to give his sugar baby a used car or something if they needed one at some point, etc. i know it sounds over the top but it's intentional. his idea of being a sugar daddy would be very irresponsible most of the time and would probably lead to issues with his family later.
*hooking up is optional, it'd be sort of funny if he was originally using it as a way to get into their pants and then it incidentally became more of an emotional friendship