-If you are going to add romance to the game make sure that the other people at the table are OK with that. Regardless of how you intend it thereis the possibility that someone can become uncomfortable with it to the point that it would disrupt the game, or that it will result in a level of silliness that would also disrupt the game.
- Start with flirting. Ryan had some suggestions on flirting (significant looks, lingering touches, unneccesary but mild compliments). If you are unsure how to roleplay this just say "the merchant's daughter/son seems to be flirting with you" etc. If its PC initatied and you want to do rolls for it you can always make it a function of Diplomacy/Sense Motive to see if intentions are communicated in a socially acceptable non-offensive way. Unless of course those involved are not overly concerend with social rules in which case it can simply be leaning over with an ample display of cleavage/leg or other obvious signs of interest and a glance out the backdoor.
-Build to the early stages of Romance that are filled with excitement. This is the stage for the secret meetings in the garden, the inappropriatly timed vists, and noticing rivals. Depending on the participants and the setting these can simply be moments of standing far too close and whispering endearments, to kisses, on to more elaborate physical acts. The latter need not be spelled out and can simply be "She shows you exactly how much she has missed you" should be sufficient for most players.
- From here things can go lots of ways, depending on setting and players. PCs that move around alot may not want to go past that point. Orcs can raid the village and capture the love interest. Parents can object. Prearranged marriages can suddenly come to fruition. If the PC isn't interested it might result in a gilted lover seeking revenge, or a dozen male relations looking for the PC's head. Or maybe the PC wants to pursue the relationship long term and the parents (or other authorities) apporve - but wants signs of the PCs good intentions. Things like a dowery (there goes the treasure from the last dungeon), conversion to the family's god(s), trials to win an acceptable level of nobility to marry in to the family. As with anything else, if you ask the PC to give something up they should get something in return to help maintain the balance. A dowery and a forced conversion, done well, might net the PC a lot of new contacts, resources, positions earned by nepotism, and the possibility of low interest loans for a favored nephew-in-law. Or if the intended's family is of simpler means it might be places to hide out, to leave loot before the tax man sees it, intelligence about the country side ("When you get to Redmont look up Cousin Barney, he knows everyone in them parts."). Either way joining a family can bring with it new responcibilities, rivals (old lovers even), feuds, debts, curses, etc. All of which can lead to new adventures.
And thats what it comes down to, in an adventure game everything should lead to an adventure of somekind. It need not be the typical combat oriented one- it can be all roleplay, but is should be an adventure.
