Garran: I suspect that no one has written one simply because it isn't all that necessary: there are five potential romances (Katie, Esmie, Joel, Thomas, and Aeolus), and wooing any one of them is mostly a natural process of making a good impression by whatever means is appropriate to the character. (And not making a bad impression by whatever means are inappropriate...)

You can propose by having and offering 'the one and only' ring. (You can potentially propose to more than one person if you find more than one of those rings - but it doesn't end well.)

cbingham: The hardest thing may be finding the rings.

There are 4 rings that I know of (so you can't propose to all 5 of them in one playthrough). 3 of them are in the sea caves. One of them is in the catacombs, in an alcove near the Paladin Memorial.

Other than that, I don't think it's that hard to make them happy. The most important thing is to do their side quests. That will REALLY increase how much they like you. Other than that, just be nice to them, learn about them, and give them gifts that they want or do things that they want (i.e. play music with Aeolus, or if you're in the rec room, play that person's favorite game). Once you got them up to "Buddy" or "BFF," you should be able to propose to them. Finally, "Say something loving" at the end of the game and declare your love for the person you proposed to, so that you can end the game on one last date with him or her, or if you proposed to more than one of them, you can see my favorite ending in the game.