Cambridge graduate Rurik Jutting also filmed the torture of one of his victims on his phone, his Hong Kong murder trial is told.
A second woman was found in a pool of blood on his living room floor, with her throat slit.
Rurik Jutting also filmed the torture of one of his victims on his mobile phone, the court heard.
He is also said to have recorded mobile phone footage describing how he had enjoyed the killing, and could not have done it without cocaine.
The 31-year-old admits manslaughter of the two Indonesian women on the grounds of diminished responsibility, but denies murder.
Judge Michael Stuart-Moore warned jurors at the start of his trial on Monday that they would hear “very disturbing” evidence.
He said there were “particularly horrifying aspects to this case, with one victim subject to extreme violence and cruelty amounting to torture” before she died.
“The defendant even recorded on his iPhone part of the torture he inflicted on his first victim,” he added.
Sumarti Ningsih, 23, and Seneng Mujiasih, 29, were found dead in Jutting’s upmarket Hong Kong apartment on 1 November, 2014, after he called police in the early hours of the morning.
Sex toys and cocaine were also found at the flat.
Jutting has pleaded guilty to a third charge of unlawful burial over the concealment of Ms Ningish’s body, which was found wrapped in plastic sheets and blankets inside a suitcase on his balcony.
Prosecutor John Reading told the court Ms Ningsih was tortured for three days in the apartment before being killed in the shower with a serrated knife.
He said she had previously had sex with Jutting at a hotel for an amount of money, but had offered to refund half the cash if she was allowed to leave early because he treated her violently.
She had reluctantly agreed to meet him again on 26 October for another, unspecified, amount of money.
Jutting met Seneng Mujiasih for the first time in a bar on 31 October, and brought her back to his apartment after offering money for sex, the prosecution said.
Before going out to meet her, Jutting bought a small blowtorch, plastic ties and a hammer, and hid two knives under sofa cushions, Mr Reading told the court.
“In one of his interviews with the police, the accused explained how he went out that evening hunting for prey, and that Mujiasih was his prey,” he said.
Jutting was born in Surrey and graduated from Cambridge University before joining Barclays in London in 2008. He moved to Hong Kong in 2013 to work for Bank of America Merrill Lynch as a securities trader.
He was brought to court under armed police escort on Monday and led into the glass-screened dock in a dark suit, looking noticeably thinner than at previous hearings.
He spoke only once to enter his plea, telling the court he was pleading “not guilty to murder by reason of diminished responsibility but guilty of manslaughter.”
He has been evaluated fit to stand trial following psychiatric tests, and is currently being held at a maximum security prison.
If convicted, he faces life behind bars.
The case is expected to highlight the former British colony’s inequality and the privileged lifestyle of its wealthy expat elite.
Both victims had originally come to Hong Kong to work as maids, and were among the more than 300,000 migrant domestic workers employed in the city. The vast majority of them come from Indonesia or the Philippines.
The trial is expected to last three weeks.