The game is very much a serious game in that it has an immense story, and is a very carefully balanced game, such that decisions you make in chapter 1 and 2 can have visible effects on how things play out in chapters 3 and 4. You have limited money, and experience and no way to grind for more. There are no random encounters, all encounters are on map, and don't respawn.
As I commented recently, I had a grand old time with an excel spreadsheet for three hours calculating how I wanted part of the story known as the Council of Gawnfall to play out. If you aren't willing to spend hours on this as a legit RPG, this probably isn't the game for you.
You can play it anyway with a cheat engine so you don't have to worry about such things, but since you're worried about seriousness I wouldn't. It's hours and hours and hours even if you cheat. The sex is baked into the world, and makes perfect sense storywise, which I think is wonderful, but that also means you have to pay attention to the story. If you want something quick or simple, this is definitely not it.