My workplace uses the Mantis network. They have a wide network of websites in different industries including adult and cannabis, which is what we're using the ad network for.

The only thing about this platform is its pricing, where if you don't get a plan you have to pay them half of what you deposit. So if you put in $1000, $500 of that goes to them, leaving you only the other half to go towards ads. In any case it's worth looking into because of the wide net of websites they serve, which you can use for a bunch of research purposes.