If you do a search of the forums on romance and relationships you’ll find an awful lot of topics on the subject. I’d suggest looking over those and feel free to bump them if you want some more input.
How Desireable are Relationships and Romance Options: Are They Considered Mandatory Crunch or Appreciable Fluff? for instance.
If you’re speaking of your own game in particular, then you can ask on its thread. You don’t need to contain romance in your game.