It takes a long time to get them in the mood, but if you meet any of the Town NPCs while exploring the floating islands, just spam whichever Allure option that makes them react with "Not bad" until hearts appear. Then you can boink them just like anyone else! Shale actually has quite a long dong, too.
But yeah, as far as scripted dialogue-initiated sex scenes go inside of Town, Sophia is still currently the only one.