If you go DIK, you can safely romance Sage, eat at the restaurant, bang most of the HOTs, have Nicole/Envy, have Jade, Have Cathy, and ultimately will be (at least for now) a Sage ending.
Neutral, you can romance most everyone so far, bang some of the HOTs,(including Quinn) have Jade, have Cathy, and then you have to refine yourself to get a final ending (just guessing here, but would bet money on it)
Chik route you can have sex with Sage at least a little, can end up with Maya and Josy, end up with Bella, end up with Jill, and have sex with Quinn(but you do have to smoke a joint).