I don't know anything about this case and please don't read this as excusing what's happened. But sometimes sex games must go wrong, so how do the police etc tell the difference? Or would they prosecute you even if it was a sex game gone wrong?The old ‘rough sex gone wrong’ defence from him then?
Here’s an interesting article on that defence that I read a while back, it also lists cases of when this defence has been used and the verdicts that were received:
Does claiming a "sex game gone wrong" work? — We Can't Consent To This
In the UK, at the end of 2018, there was a great outcry at the sentencing of the partner of a young woman, Natalie Connolly, to 3 years and 8 months for her manslaughter. He’d claimed in his defence that Natalie had consented to “rough sex”, including beating and to sex acts that caused her terribwecantconsenttothis.uk