During a hearing at Sheffield Magistrates' Court today, Harnick Kang, 42, pleaded guilty to committing an act of outraging public indecency, to a count of racially aggravated harassment and to another of using threatening behaviour.
David Marshall, prosecuting, told the court how Kang's offending came to light, when a passenger on board a Cross Country train to Sheffield on August 5 last year went to use the toilets and found Kang engaging in lewd behaviour in the train vestibule.
Mr Marshall said: "He was confronted by the sight of the defendant with his trousers down. His genitals were exposed and a female was knelt down. The complainant was concerned by what he had seen. He filmed a video of what happened on his mobile phone."
The complainant in the case reported the couple's lewd behaviour to a train manager, who later found them in another compromising position - this time in a train carriage.
"The train manager said they both had their trousers down and she was bouncing up and down on his lap," said Mr Marshall, adding: "He confronted the couple and was pushed away by the defendant and was told to 'f*** off'. He made his belt into a makeshift noose."
Following this, the train manager 'backed away' and reported the incident to British Transport Police, who were waiting for Kang when he arrived at Sheffield railway station.
Mr Marshall said: "British Transport Police spoke to them both and both the male and the female were abusive and were shouting and swearing."
Kang started hurling racist abuse at the officers, using terms such as 'white b******s,' the court heard.
He was subsequently arrested by officers at the scene and began banging his head against the perspex window in the police van.
Defending, Brandon O'Leary, disputed whether Kang and his female companion had actually had sex while on board the train.
The 'outraging public indecency' charge refers to Kang displaying his genitals and attempting to have sex.
His female companion has not been charged with any offence.
In mitigation, Mr O'Leary told the court that in the run-up to the offences taking place Kang, of Stenson Road, Sunnyhill, Derby had received some 'very distressing news' about his mother's health.
Mr O'Leary said: "He had gone out for the day with a friend. He cannot explain his behaviour. He says it's unacceptable. He would have been shocked if he had seen someone doing what he was."
He added: "He's a businessman in Derby, he's a property developer, he's an upstanding citizen who gives money to charity, and tries to better society."
District Judge Naomi Redhouse adjourned the case until later this month to allow for a pre-sentence report to be prepared, and granted Kang bail until his next court appearance.