Nothing happened. All that happened really is that I faught Lin Lin in the underground figting place and made her masturbate and now her masage place is lined up, and found the other cow in the gentlemen club, bought all the items from her and she disappeared. Nothing else happened down in the slums.
Here's the main steps:
-talk to Fawn in the condo, get the Cassie rescue notes
-go round talking to NPC's that you have good relationships with, and get their help.
-Specifically talk to Arlene, then go to the hobo area in the slums
-get the hobos' help (make sure they actually deliver, and you'll need to sleep to move the clock forward,) then return to Arlene
-after that you can rescue Cassie!