Re: different/default types of sims's attraction
First of all, the default in a fresh save is that everyone has no romantic attraction, is sexually attracted to everyone, and is exploring. This means they're open to developing into the orientation you want them to be based on the romantic interactions they perform, and whether they accept the romantic interactions of others.
Er, game-mechanic-wise, romantic orientation involves whom your Sim will accept romantic overtures from, and woohoo orientation involves whom your Sim is willing to woohoo with. For a lot of players, this is the same thing, but it's not necessarily. Some examples:
1. My bestie is panromantic asexual. That means she feels romantic attraction to any gender but doesn't want to "woohoo" with anyone.
2. Some folks are aromantic, which means they feel no romantic attraction to anyone but still want to "woohoo." "Ask to be woohoo partners" was intended for that scenario.
3. My black widow was "straight" in that she was romantically attracted to men, but she married Nancy Landgraab for the sweet, sweet Simoleons and they did "woohoo." (Geoffrey just wasn't into her, alas.)
I could go on with more examples, but I think you see what you mean.
(There's also a bug where a lot of townies are generating aro-ace. I don't think this is what you're asking, though. https://answers.ea.com/t5/Bug-Reports/OPEN-Townies-with-no-Sexual-Orientation-at-all/m-p/11671407#M221610)
