A young woman who found Irishman Adrian Murphy on Grindr and fatally poisoned him in London using the date-rape drug scopolamine, known as ‘devil’s breath’, has been sentenced to 16 years in prison for his murder.

Diana Cristea, 19, helped and encouraged her boyfriend, Joel Osei, 26, to target men using the gay dating app. The pair’s plan was to rob the men and empty their bank accounts.

In the summer of 2019, Osei killed 43 year-old Adrian Murphy, a dance teacher from Kilkenny, with an overdose of the drug. Afterwards he, along with Cristea, attempted to buy $80,000 worth of diamonds from a jeweller in New York.

The Irishman died between being contacted on Grindr and meeting Osei on 1st June and when his body was found by his best friend in his London apartment on 4th June – the exact day was not concluded. His phone had been thrown down the toilet, while a can of Coca-Cola was found to contain traces of scopolamine and Osei’s fingerprints were discovered on a bottle of whisky left at the scene.

Cristea, of Langley Park, Mill Hill, London and Osei, previously of Kerswell Close in Seven Sisters, north London, were both found guilty of murder following a trial at Croydon Crown Court. They were also convicted of poisoning another man found through Grindr with the same drug two days earlier. That victim, who cannot be named for legal reasons, survived the incident, but was taken to hospital after being found by a neighbour almost naked, extremely agitated and confused.

On Monday, Cristea was sentenced to life in prison with a minimum term of 16 years. She was also convicted for her part in drugging the other man and given 30 months to run concurrently, with no further penalty for fraud and theft offences.

RTÉ reported that during sentencing at Old Bailey, Mr Justice William Davis acknowledged that Cristea was just 17 at the time of the crime but said: “You were an active and willing participant in this plan. You expected to gain from this plan. You knew scopolamine was being used and knew what it could do.”

Adrian Murphy was a gifted dancer and had worked as a dance teacher and a choreographer at the Royal Academy of Dance, but was on a year-long sabbatical at the time of his death.

In a statement, his sister Majella Murphy told Cristea that she had been “torn in half as a direct result of your selfish and despicable actions”.

She said: “You stole my little brother Adrian from me and as you are a woman, your actions are even worse than your partner in crime and a complete disgrace.

“It’s very difficult for me not to hate you, but I refuse to hate you and refuse to be like you, so I must forgive you.”

In January, Osei had been convicted of murder and jailed for life with a minimum term of 32 years. He was also given a concurrent jail sentence of five years for administering a poison to endanger life against the surviving victim, and no separate penalty for multiple counts of theft and fraud.