Unless you have specifically set it in CAS then Sims you created or was born in game will be undetermined until you do something romantic with them. Random townies will also be undetermined.
Unfortunately, that isn't true. Many random townies are set to no romantic interest, not exploring, and no woohoo interest. That means they refuse all attempts at romance and woohoo unless you use cheats to take them into CAS and modify those settings. See the bug report below for more details.
https://answers.ea.com/t5/Bug-Reports/OPEN-Townies-with-no-Sexual-Orientation-at-all/td-p/11671407
I am not having this issue. I have townies that I actively play that have interest and I have to go ti Cas to find out what they are.
