You've definitely got a Civilization type game with an extremely adult bent. Well Done! I have one "bug" report, and a recommendation.
Regarding Marcus and Paradise, one of the methods to get in good with Lusty, Beauty and Crazy it to "kill" Marcus. When you talk with him, he gives you his amulet to "prove" he's dead, saying "I trust you enough to hand it over to you but do me a favor and return it, the necklace has some sentimental value for me".
However, once you use it and ultimately defeat Paradise, there is never an option to give the Amulet back and close the storyline. He still shows up in the Diplomacy section saying here's the Amulet.
For a recommendation, I found the battles got too easy after a certain point. While it is an awesome feeling to know that you and your army can defeat anyone you come up against, it get's a little boring after a while. I had probably about 1/4 of the screen under my control when my army reached invincible level. At that point, I just went straight for the Capitals of the other territories, easily conquering them.
Might I suggest a scalable strength of the opposing army? So if your army is at one level, then the opponent can be 1.25 times in strength. Or at least the same strength? Or maybe a random strength to make it variable. This might make it a bit more challenging the whole way through.
I did like the option to use Intelligence to have the option to provide an Ambush, thus not risking your army. I don't think I've seen that in any other game, even Civilization(Granted, it's been years since I played that).
In closing, the game has a good balance to it. VERY well done.