I don't believe what happened to Shia Laboeuf was rape because I don't believe sexual assault by a woman on a man should be classified as rape. In his circumstances it seems he was physically assaulted (he said she whipped his legs for 10 minutes) then sexually assaulted. Consent isn't an issue for the physical assault though it is an issue for the sexual assault. As MEOD says, consent has to be specific, not generally given (although a woman would be almost certainly raped if she did the same thing and can you imagine how she would be treated by the press and court of public opinion).
As far as I can see, it's not clear why Shia Laboeuf seemingly did nothing while she whipped him and then sexually assaulted him. His team said they stopped her as soon as they became aware and sent her out.
I am not comfortable with the comparison of this incident with women's responses to rape. The rape myths addressed by the We Believe You campaign are highly specific to women, the way we are socialised to be the gatekeepers of sex but also to accommodate men:
www.mumsnet.com/Talk/womens_rights/a2246812-Shia-LeBouf-rape-sexism-at-its-fineist?msgid=51071324
Bidisha wrote about the myth that if women didn't struggle or fight back it wasn't rape:
www.mumsnet.com/bloggers/bust-rape-myth-bidisha
I agree with everything she said but I see that as a combination of very rational fear of physical violence together with shock and also socialisation and not knowing how to respond to a violation.
It seems a natural question to ask why a person does nothing while they are being assaulted however we can see through women sharing their experiences that we understand why women don't fight back and we shouldn't question any particular woman about how she responded to a rape (although the police do). We know that by asking this question when a woman has been assaulted, she feels shame and responsibility so we shouldn't ask. I agree the onus should be on the rapists' behaviour.
I have no idea why a man wouldn't react though. They are not subject to socialisation that they should provide sex to women, nor that they should fear violence from women. I accept that they are socialised that a man would take sex from any woman who offers (not the same thing though). They are not told they provoke rape by their clothes, that a strange woman might attack them at night or that men often lie about rape.
This makes me uncomfortable with an expectation that the principles of the We Believe You campaign should apply to men. I don't think, for example, that a man allowing himself to be whipped for 10 minutes then sexually assaulted for the sake of artistic integrity (of maintaining silence and passivity during the performance) should in any way be compared with the experience of women who are raped by men. I don't know if that is what happened but it seems to be a reasonable possibility.