Most guys certainly would react as if something was different... they might think "Uh, what's this crazy half-naked thong lady doing sitting next to me at work?" But lets say for the sake of this argument that they do happen to be excited by what you're wearing, and start to flirt... does that somehow mean they are likely to rape you? Of course not. I don't have the statistics, but I'd wager that most healthy males are more turned on by the idea of a woman being turned on to them. There's a reason so much pornography depicts the women as enjoying whatever happens, hence all the fake [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse]. The fantasy of the man appears more a desire to be be wanted by the woman, and to please her. Rape isn't about that at all. Rape is about violently going against a woman's will. To hurt her. She might be injured, cry bloody murder or any number of things. The rapist would be the one to cause this pain. While I cannot cite a particular study, I'm pretty sure most men do not want to assault the women they are attracted to. I know I sure don't.
Anyway, unlike lingerie, bikinis are not made to indicate a state of sexual intent, or to entice in the bedroom.. So, as a stright virile guy, while I might think "Wow, she's pretty", I'm certianly not going to think "She wants to have sex with me". Big difference there.