Pc Gordon Semple shared an interest in sado-masochistic sex with his alleged killer, Stefano Brizzi, jurors at the Old Bailey were told.
On April 1, while he was on duty, the 59-year-old officer arranged to go to Brizzi’s flat on the Peabody Estate in south London for sex.
Hours later, Brizzi, 50, was allegedly in the middle of throttling him when another man turned up on his doorstep.
The man, referred to as CD, had gone to take part in a sex party with drugs, but the defendant put him off by saying someone was “ill”, the court heard.
Over the next few days, neighbours noticed a “revolting smell” coming from Brizzi’s flat.
When one complained, Brizzi put it down to cooking for a friend.
By April 7, a neighbour alerted police, who visited the flat and found Brizzi wearing only sunglasses and underpants.
They also found a bath full of acid with “globules of flesh” floating in it, the court heard.
Brizzi allegedly told an officer: “I’ve tried to dissolve the body ... I’ve killed a police officer. I killed him last week. I met him on Grindr and I killed him. Satan told me to.”
However, jurors were told that the defendant was not claiming a psychiatric defence and now says Pc Semple died accidentally during a “sex game gone wrong”.
Brizzi denies murder but has admitted a second charge of obstructing a coroner in the execution of duty between March 31 and April 8 2016.
Opening the trial, prosecutor Crispin Aylett QC told jurors the case called for “broad minds and strong stomachs”.
Pc Semple had been in a relationship but was “sexually promiscuous” and used Grindr for “extreme” encounters of “domination, bondage and much else besides”, he said.
On April 1, he sent a message to Brizzi saying “free now for hot dirty sleazy session” and went to the defendant’s flat, the court heard.
Mr Aylett said: “Over the next few hours, both Gordon Semple and the defendant used Grindr to invite other men to come to the flat for a sex party where drugs would be available.
“Although a number of invitations were sent out, only two men responded with any real interest.
“One was put off by the possible use of drugs and he decided not to go, the other got as far as the front door of the block of flats in which the defendant lived.
“When CD pressed the entry buzzer, someone who can only have been the defendant replied over the intercom ‘We are having a situation here. Someone fell ill but we’re taking care of it. So our party is cancelled’. CD turned around and went home.”
Mr Aylett went on: “In fact, it seems clear that there had only ever been two people in the flat - the defendant and Semple.”
Pc Semple’s last communication on Grindr was a few minutes before at 7.04pm, the court heard.
Twenty minutes later, his partner tried to call his mobile phone but got no response. He later reported him missing.
The prosecutor told jurors that CD must have arrived at the very point Pc Semple was meeting his death inside the flat.
Brizzi later told police that Pc Semple had invited a number of people to the flat “but they didn’t arrive and, when one did arrive, I was right in the middle of strangling Gordon and I said to - he was right there at the door - and I said to him ‘Look, this is not the right time now, people are falling ill and it’s a mess’.”
The court heard that Brizzi had been a user of crystal meth - referred to as Nutella - which had cost him his job.
He allegedly told a support group that he believed in the Devil, and liked “satanic rituals” which involved having sex over the sign of the pentagon.
He liked to boast of his sexual exploits and told one meeting he had once tied a man up, treated him like a dog and made him go into a cage, jurors were told.
Brizzi was “obsessed” with the American show Breaking Bad, the court heard.
Mr Aylett said the main character, chemistry teacher Walter White, produced crystal meth and, after poisoning a rival, dissolved the body in acid.