I appreciate your comment and totally respect your opinion. And I totally understand why you might not like the direction some characters took.
But just wanted to say that it is entirely intended for Laz to be a terrible human being and treat others terribly. Which is made to contrast with how she normally act when it's unrelated to sex.
In a way : she's kind of become a slave to her own urges after experimenting on herself too much (and the cumcoction kinda was the trigger to all of that considering she didn't do anything before even though she might have been able to)
This won't ever explicitely be explained in the game though but I figured I'd mention it.