The MI6 spy whose body was found in a padlocked hold-all in his bathtub sometimes went by a name other than Gareth Williams, his inquest has heard.
But his mystery second identity was not revealed as the coroner cut short the line of questioning to a friend of the 31-year-old.
Elizabeth Guthrie was asked by Mr Williams's family lawyer Anthony O'Toole whether the spy had told her he "sometimes used another name", to which she replied "yes".
She also revealed that Mr Williams had used a number of different phones to call her, but more often than not he would "just show up and ring the bell".
Ms Guthrie, who signed a police statement on which her name was also incorrect, described a friendship with Mr Williams based on their mutual love of history, art, Japanese Manga cartoons, travel and humorous anecdotes.
Mr Williams's body was found in his Pimlico flat in London in August 2010 but, 20 months on, the circumstances of his death remain a riddle with police finding some £20,000-worth of expensive women's clothing and shoes, the inquest at Westminster Coroner's Court has heard.
Ms Guthrie, who said she had never been to Mr Williams's flat, added she and Mr Williams had been planning to attend a fancy dress ball together, dressed as luridly coloured Manga characters.
Asked if her friend had ever expressed an interest in cross-dressing, Ms Guthrie said: "Nothing of a sexual bent but we were going to a fancy dress ball together; he was going as a ninja, not as a queen," adding: "I have a personal view that he was straight."
Questions were also raised about whether Mr Williams's work computer could have been tampered with by the Secret Intelligence Service (SIS) after the spy's body was discovered.
The electronic equipment was handed to Scotland Yard's counter-terrorism command, SO15, on August 27 - four days after his death came to light, the inquest heard, and Mr O'Toole noted there was not "any statement from any person at GCHQ to say that equipment was not tampered with" in the interim period.