No, as far as I know you always get a darker jewel when you make the Offering to the Darkness, with certain exceptions, the main one being rape. The books do have certain amount of sex in them, but I was going to forgo that in the campaign world, save for a few mentions of "broken" NPCs. That, and if any of the PCs get involved with anything like that, they then end up having to deal with the NPC characters from the novels, who are up there on the power scale.