The government has published a new clause to its Domestic Abuse Bill to end the so-called "rough sex defence".
The amendment would rule out "consent for sexual gratification" as a defence for causing serious harm, in England and Wales court proceedings.
Justice Minister Alex Chalk promised last week to amend the bill to make clear such a defence was unacceptable.
Labour's Harriet Harman said the new amendment was a "milestone" in ending violence against women.
Campaign group We Can't Consent To This, which wants to make it the expectation that murder charges are brought against those suspected of killing a person during sex, hailed it as a "victory".
The current law says that if someone kills another person during sexual activity they could be charged with manslaughter alone, while to murder someone, there needs to have been an intention to kill that person or to cause them grievous bodily harm (GBH).
The amendment would invalidate any courtroom defence of consent in cases where a victim suffers serious harm or is killed.
Harriet Harman called the addition to the Domestic Abuse Bill, signed by Home Secretary Priti Patel and Justice Secretary Robert Buckland, a "milestone moment in battle to challenge male violence against women".
She tweeted: "This will stop men literally getting away with murder by saying it's what she wanted."
The new bill, covering England and Wales, is due to become law later this year.
End to 'lighter sentence'
We Can't Consent To This has collated 60 examples of women "who were killed during so-called "sex games gone wrong'" in the UK, since 1972.
The group claims that 45% of these cases ended in a "lesser charge of manslaughter, a lighter sentence or the death not being investigated as a crime at all".
There are also 115 people - all but one of whom were women - who have had to attend court where it is claimed they consented to violent injury, the group has said.
Mr Chalk said: "No death or other serious injury - whatever the circumstances - should be defended as 'rough sex gone wrong'.
"Perpetrators of these crimes should be under no illusions - their actions will never be justifiable in any way, and they will be pursued rigorously through the courts to seek justice."