The plot is that you gain a mansion staffed with some maids along with a huge debt that comes with it and you need to… well man up and fix it or die (apparently your body is collateral for the yakuza or stg) Now the debt never comes into play during the game which is somewhat sad since I guess it would make the game a bit more challenging. Items and patches from CM3d2 are compatible mostly with Com3d2 and vice versa. With some small differences, instead of 1 custom maid you have 3 and the characters are slightly different. The game follows the path of its predecessor CM3d2…. For the vanilla game I am not sure how the dating simulation works.
The game is an anime character generator + empire running simulator in the vanilla version complemented with some mini games eg idol dance, blackjack, slot machines and a dating simulation.