I'd like to emphasize this point and add to it. A "turn off" is not only sexual, nor even exclusively related to different genders, or to sex. I can say "People with bad manners turn me off" or even "The hard-sell approach in promoting a product is a real turn off, for me" or "This music really turns me off."And to turn you off/on is not exclusively sexual. A woman might say "It's a real turn off when a guy talks about himself all the time." It's a real negative in the way I look at him, maybe sexually but more just in general.