Leopold Leisser, also known as the German Master, started his testimony in the Shrien Dewani trial.
He is a gay escort specializing in S&M and Dewani had used his services three times.
Leisser explained that he started his business in 2009 and never allowed clients to sleep over.
"But [Dewani] was the first client to sleep over," said Leisser.
Before he could continue to speak about their liaisons Judge Jeanette Traverso interjected : "What is the relevance of this testimony?"
State prosecutor Adrian Mopp was at pains to convince her that Leisser's evidence would shed light on the motive of the murder.
He said Dewani allegedly told Leisser that he was at a cross road about getting married.
But Traverso said Dewani had always been open about his sexuality and that it was of no relevance to the case.
Leisser's testimony was suspended.
Dewani is on trial for his wife's murder in 2010.
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