Turn-offs?
Any kind of violence or abuse (actual or implied).
MMF
Prominent tattoos
Body piercings, especially genital!
Any kind of anal sex
Long painted nails
Lingering close-ups of the dude's face. (I'd just as soon not see his face at all; it's the girl that interests me).
Anything particularly scatalogical
Clown sex
(remember watching Bambi Bliss in clown make-up...what a turn-off)