Can't have this list without mentioning the Bothrioc Quadommes on Myrellion now. Running into the quadommes at full egg/oil addiction triggers a bad end. It's a waste if you let the pidemme's get your there though. The scenes with the Quadommes change the worse off the PC is, so there's a decent build-up.
Only complaint is that final scene is a bit light on specifics of the PC's transition into debauchery. Not devoid of it, just light.
That, the alpha Nyrea, and Jerynn provide the absolute best bad ends in the game because of the slow fall and how much the character falls into things.
In defense of Jerynn's bad-end, it triggers first by accident in theory. Everything else she acknowledges as telling the PC they can stop putting themselves in harms way if they want to be her pet. The writing is not completely unaware of the weirdness of it. That said, it is still a not-so-great way to force the encounter, and is hard to defend in an RP aspect.
Glad there's another enthusiast on the forums. Bad-Ends Best Ends.