Majority of romantic interaction options are missing?

I just got my Sim into a relationship with an NPC, and I noticed a lot of romantic interaction options just aren't there. I tried removing my mods to see if that was the issue; it wasn't, the interactions are still missing. There's only like, two or three options for each category. He can't ask her to be his girlfriend, the "First Kiss" option won't show up, hell they can't kiss at all! I looked through the Relationship tab, all he can do there is ask her about her orientation and stuff. I've never had any issue with romancing NPCs in the past. They're not related, they're both young adults, and they don't have any conflicting orientations. There's no reason why they can't be in a relationship. Their romance meter is halfway filled and the game just isn't showing any of the extra romantic interaction options. I can't find a solution anywhere online, wth's going on?