Laura Hamilton with Anita Blake. What she turned her into makes my eyes bleed. She took a strong interesting female character and turned her into a blow up doll for the past 5 books. There is no plot anymore, just sex.
Really, I have no problem with erotic novels. Really. Her books are an abomination because of what she turned her main character into. If she had kept her interesting and said as a side plot that she has lots of yummy sex when the mood strikes I would have been all "yeah girl, get your groove on!" but she makes the books all about the sex. Who she's going to have it with, when will she have it, oooooh, look, she's having sex, hey, she just had sex, wow, having sex again, huh?, that must chafe by now.
John Grisham. He has written the same law novel umpity times now. The first three were great, the rest have been a rehash with different names. Same with Robin Cook. They became too formulaic.