Parts where I got stuck and found solutions through many pages of forum posts and trial and error
Act II: (I think it was act II, the part with the stripper demon) You have to approach the stable from the right path to trigger the even. Approach from the bottom right not up top.
Act III: You have to encounter 3 different areas where girls have gone missing, then go do just about anything at the fair to make it night time. You can only encounter one girl having gone missing per day.
Act IV: The elevator is in the middle of the first floor, doesn't look like an elevator. Ran around for hours trying to get levers to move. From what I gather, once you flip the green lever you can access the elevator in the middle of the first floor. (I flipped the green lever then ran around for an hour trying to figure out where to go next)
Act V: After you defeat the leader of the cultist in the mansion, leave to get to the cliff side area, then come back into the building to access the secret room that has a teleporation circle that takes you to Dermont's office to open that chest in his office. The key to the right door of the sex temple is inside. Bring 10 maiden's Honey to the sex temple. Needed for virgin ending.
Since the game stops being translated near the end, the last town is difficult to figure out, just talk to your familiar after each scene, he will advise in English.
To do jobs you have to have the entire correct outfit, head included. I know the Dancers set is needed to be a stripper. Pretty sure there's a bunny set for being a waitress (haven't tried this, but all the girls there dress that way). Think the underground area wants a collar or something. You can usually tell where your needing a certain outfit in the last town as outfits are usually displayed in red text by the npc that gives the job.