Depends what you mean by "defending".
I think he was stupid to put himself into this situation, given his fame and potential for exactly this to happen.
I don't think he should be charged with any crime, nor should he be civilly liable for anything. She not only asked for this stuff, but she came back a second time for it. Clearly there was consent, even though it ended up causing some physical harm. She got exactly what she was asking for and wanted, then cried foul when (gasp) it turned out to cause injuries.
The only person she should blame for this situation is herself.