An academic at the University of Leeds has been accused of having sex in his office while a counselling session took place next door.
A hearing was told today that Dr Alec High, who lectured in dentistry, repeatedly engaged in sexual activity on the university premises despite warnings over his conduct.
One one occasion, he is alleged to have been overheard with a woman as a colleague comforted another student who had recently lost a family member in the adjacent office.
At least four members of the university's staff told the General Dental Council's practice committee that they had heard the liaisons taking place, and had spotted his sexual partners entering his office.
His alleged dalliances are said to have continued for more than two years, and even though a senior colleague told him his behaviour was not acceptable he carried on, the committee heard.
Dr High even allegedly lied to a university investigation into his activities, trying to convince staff that he was working at St James's Hospital at the time it was claimed he was having sex with a woman in his office at the school of dentistry.
But it was found his computer equipment was logged on and connected at the Worsley Building, where his office was based, the committee heard.
Dr High was charged before the committee with repeatedly engaging in sexual activity between January 1 2013 and March 11 2015, and again between 2pm and 3pm on March 12 2015.
He is also accused of inappropriate and unprofessional behaviour, and of giving a false account of where he was on March 12 2015, which is said to have amounted to misleading and dishonest behaviour.
The allegations of sexual activity came to light after a student support, advice and outreach officer at the university complained about Dr High having sex while she tried to console a student in March 2015.
Tom Coke-Smyth, on behalf of the GDC, told the committee: "During the appointment she began to hear the loud noise of what she was clear was two people having sex.
"This occasion was particularly serious as she was dealing with an upset student who had suddenly lost her grandmother, whose family was abroad and who was unable to return home for a funeral."
The committee was told that she and other staff, including lecturers, had overheard Dr High having sex in his office for years.
When she complained to her boss, a professor, in summer 2014, he confronted Dr High and was promised it would not happen again.
Dr High became "embarrassed" whenever the support officer walked past him and he refused to speak to her.
But after the professor left the university in December 2014, the liaisons started again - at first in the evenings and then in working hours.
When an investigation was launched, Dr High lied about where he was on March 12 2015, claiming that his computer history would prove he was covering for a colleague at St James's Hospital, the GDC heard.
But when he was told his computer equipment would be examined, Dr High protested that was "completely unacceptable", becoming "increasingly agitated at the prospect".
The investigation found his PC, laptop and mobile phone were all logged on or connected at the Worsley Building during the time he was accused of having sex.
Mr Coke-Smyth said: "The result of these matters is that it is alleged that Dr High's actions in engaging in sexual activity in his office were inappropriate and unprofessional."
Dr High, who did not attend the hearing in central London, is a highly experienced dentist who worked for the NHS in north-east England before joining the University of Leeds in 1981, teaching undergraduate and postgraduate students.
The hearing continues.