Jennifer Elliot, who rented a flat in Cheltenham to Gareth Williams, said that she and her husband had heard him shouting for help one night about three years ago.
She said that they found him with both hands tied to his headboard. He was dressed in boxer shorts, she added.
“He said: ‘I just wanted to see if I could get myself free,'” Elliot said in a statement read to the court. “He was very embarrassed and panicky and apologising.
“My husband said: ‘What the bloody hell are you doing?’ He said he was just messing about to see if he could get free.”
She stated that Williams did not appear aroused but that “my husband and I discussed it and said it was more likely to be sexual than escapology or similar but cannot be sure”.
The inquest has already heard that Williams had £20,000-worth of womens’ clothing and shoes in his flat, and searches of his home computer seized after his body was discovered showed that he had visited “websites of claustrophillia, and he also had access to bondage and sado masochism websites”.
However, it has also been revealed that police did not retrieve electronic equipment used by the MI6 expert until five days after his death. Equipment used by Williams at MI6 HQ in London took four days, Westminster coroners court heard.
A senior counter-terrorism police officer could not guarantee that security service computer equipment belonging to Williams had not being tampered with after his death.
When asked about Williams’ sexuality at the inquest, his friend Elizabeth Guthrie said he was straight, and insisted that the designer female clothing found in his home “certainly wouldn’t have been for him”.
Superintendent Michael Broster, of the SO15 counter-terrorism command, also told the inquest that he had been unable to establish a connection between Williams’ death and his work.