Leeds Crown Court has heard how some staff members - including Karen Cosford, pictured - at Wakefield's maximum security prison are accused of being in an 'utterly corrupt relationship' with a rapist.
A prison nurse romped with a convicted rapist while colleagues stood guard and sent him text messages on his contraband mobile phone telling him 'you're generous, sensitive and dead sexy', a court heard.
A jury was told Karen Cosford, 47, had a sexual relationship with lifer Brian McBride and topped up his mobile phone for him.
The court heard Cosford sent the serial rapist a catalogue of texts including telling him 'you are my world', 'miss you so much' and 'can't wait for you to get out'.
Carolyn Falloon, 50, Jacqueline Flynn, 46, and David Sunderland, 49, who all worked on the healthcare wing at high-security Wakefield Prison, West Yorkshire, are also standing trial at Leeds Crown Court charged with one or both of the following offences - failing to notify prison authorities about the sexual relationship between Cosford and McBride, and failing to tell them McBride had a mobile phone.
Prosecutors say that, despite the defendants denying the charges, Flynn admitted during police interviews that she stood guard outside McBride's cell while the pair were inside - and heard the 'jangling' of Cosford's keys - while Falloon told police she had disturbed them having sex.
The jury heard that Cosford, who has 15 years experience in her occupation, was described as being 'touchy-feely' with McBride, resting her head on his chest, laughing and even kissing him in the prison - a notorious facility situated on Love Lane.
The court heard that McBride, a who was serving a life sentence for multiple offences of rape and violence, was in the healthcare centre as an in-patient and worked as a cleaner while he was there.
Richard Wright, prosecuting, told the court it was here that the defendants started entering into 'corrupt relationships' with McBride.
Mr Wright said: 'In the case of Karen Cosford, she had a sexual relationship with him.
'All the defendants knew that he was in possession of a mobile phone and SIM card, which were prohibited items that not even staff could take into prison.
'Falloon and Cosford purchased top ups for him in a blatant breach of the Prison Service.
'Cosford, Flynn and Falloon engaged in regular texting and telephone conversations with McBride when they were not at work.
'David Sunderland supplied McBride with a cribsheet setting out how he could access handsets and his home telephone number was found in McBride hand sets.'
The court heard that events unfolded when a search of McBride on September 25, 2009 found a mobile phone charger.
Mr Wright said McBride was put in his cell and a thorough search of the wing carried out. In the kitchen a bag of sugar was found, in which there were mobile phone top-up documents, pieces of paper with mobile phone numbers on, a photograph of a nurse who was identified as Cosford, and an unsigned love letter.
Four mobile phones were also found during the search.
The jury heard that, during the search, McBride became agitated in his cell so a number of negotiators working in the Prison Service were called - and by chance one was Darrie Cosford, Karen Cosford's husband.
Mr Wright said it was during the negotiation that McBride hinted to Darrie Cosford that he had been having a relationship with his wife.
The jury heard Karen Cosford called in sick to work the next day and over the weekend, and on September 28 reported to prison authorities that McBride had raped her.
But Mr Wright told the court her stories were inconsistent during police interviews.
Cosford told police he had forced her to write the love letter found in the bag of sugar and offered to pay her mortgage and buy her a flat.
She also said that Flynn and Falloon had stood guard outside McBride's cell while she performed a sex act on him.
Cosford also claimed McBride had forced her to text him - a claim rejected by the prosecution, who read to the jury text messages sent by Cosford.
One read: 'I'm trying to ring, engaged. D [her husband] home soon, can't believe how we get on sometimes especially this morn. We need to be really careful will try and ring later. Love and hugs me.'
Another read: 'Hope you still love and miss me like I do you. Can't wait for you to get out. Want the first time to be so special me and you xx.'
Another read: 'You are my world now don't let me down. Miss you so much. It's been a difficult journey. You're generous, sensitive when you want to be and dead sexy.'
Mr Wright also alleged that Cosford warned McBride not to use his mobile phone because prison authorities were tracing calls - something he said she would not have done for someone who was allegedly raping and threatening her.
The text message Cosford sent read: 'Don't use bone [phone] to ring anyone now... don't know what information they have and on who.'
Mr Wright said Falloon, of Wakefield, told police during interviews that she had disturbed Cosford and McBride having sex, and said that the two were always laughing together and would kiss in her presence.
The court heard she also told them that McBride offered her money to help reduce her debts if she kept quiet about the situation and helped him get mobile phone top-ups.
The jury heard Flynn, of South Kirkby, West Yorkshire, told police during interviews that McBride would rant and rave about Cosford and if she did not say goodbye when she ended her shift he would be upset.
Flynn described Cosford and McBride as 'touchy feely'. Mr Wright said: 'She saw them kissing and stood outside the cell door when Cosford and McBride were alone in it.
'She heard rhythmic noises including the jangling of Cosford's key chain.'
Sunderland, of Wakefield, continually denied knowing about the mobile phones or the relationship.
Mr Wright said another prison officer, Kevin Wilson, 57, who has admitted providing McBride with a SIM card and knowing about the relationship, is also willing to testify that Sunderland knew about the mobile phone and was McBride's 'right-hand man'.
He said: 'There was a simple motive here, greed', alleging that the defendants had been duped by McBride's claims of wealth on the outside.
Mr Wright told the jury: 'Through 2008 and 2009 the prosecution argues that roles and responsibilities in the healthcare unit were turned on their heads as members of staff allowed themselves to be drawn into utterly corrupt relationships with Brian McBride that undermined the integrity, security and safety of the prison.
'There was no doubt that McBride was an intelligent and well-practised manipulator who was an expert in inveigling his way into the confidence of others.
'We accept that he delighted in breaking down the barriers of appropriate conduct and behaviour that should have separated him from the prison service staff.
'We accept that he did so in a process of manipulation and deceit.'
Cosford denies having a sexual relationship with McBride, failing to notify authorities that he had a phone and purchasing top-ups for him.
Falloon denies failing to notify authorities about the relationship and the phone, and purchasing top-ups.
Flynn denies failing to notify authorities about the relationship and the phone.
Sunderland denies failing to notify authorities about the phone.