I might have discovered a quick way to get from friend to romantic interest

[MoMoll]

Hey Xakzen: I've never played the innapropriate trait, so don't know how it influences romance. When my sims are mad at each other (flirtying with another sim, etc.) I have them do non Romantic things first (dancing, eating out, playing chess, talking in the hot tub), then I move to the romantic. It usually works for me.

[Hosfac]

It does in a round-about way.  The Inappropriate trait gives sims special interactions and access to romantic interactions when they would be...well, inappropriate.  Like kissing an acquaintance.  Of course, if the recipient of the inappropriate romantic interaction has the Inappropriate trait as well, they're very likely to accept.

I guess you could say that it would be appropriate to sims that aren't. 

[xakzen]

...I've never played the innapropriate trait...

The brother didn't have the innapropriate trait tho arguable what he did was. The girlfriend had the innapropriate trait which allowed her to get into bed with an acquaintance. (You can tell when an NPC has the innapropriate trail  because they lick plates/bowls rather than clean them. They also eat by shoveling the food with their plates held right up to their mouths.)

[Hosfac]

(You can tell when an NPC has the innapropriate trail  because they lick plates/bowls rather than clean them. They also eat by shoveling the food with their plates held right up to their mouths.)

It's the Slob trait that does this.  It also allows you to eat spoiled food without getting sick.