I see, if Cassie has been taken by the don, try to talk about it to fawn, sleep, check fawn, then talk to Arlene (police officer), You can also ask Lin Lin or Sammy (LD+) for the guards schedule, if this is LDO, you have to buy her off the don (link for part 1 LDO Cassie's route. : https://itch.i o/t/701687/main-quest-line-lust-doll-cassie-ending-part-1 ) But for LD+, you have to break in the don's lair and get her out, there is also another ending if you get her out, you don't stay in the city and it ends, but if you rescued cassie with arlene'smhelp, you can move on with the game and also have new options for her.