Story somewhat futuristic, set in a city like "New Rome" or similar. Guy's mother (perhaps a courtesan?) marries well (to a powerful man, maybe a senator or emperor?) and he's suddenly in the limelight as heir-apparent. They originally lived with extended family who didn't usually treat them well, but now will need to adjust to the new circumstances. The story focused on him coming to terms with his new life. As I recall, there may have been a mention of a sequel, or the author may have hinted at the possibility braodly in the context of the story.
Any assistance greatly appreciated!