A 47-year-old man broke a ban on him approaching young men and touching their muscles, a court has heard.
Akinwale Arobieke, of Toxteth, Liverpool - known as "Purple Aki" - was jailed in 2003 for harassment.
Liverpool Crown Court heard Mr Arobieke asked a 17-year-old to show him his biceps - after a Sexual Offences Prevention Order (Sopo) was imposed.
Mr Arobieke denies approaching the boy and breaching the Sopo in June last year, two months after it was made.
The court heard Mr Arobieke had a "predilection" for approaching young men and touching or feeling their muscles.
His reputation had spread across north-west England and was considered by many to be an urban myth, the jury heard.
The prosecution said the Sopo was imposed in April last year and banned him from approaching males under the age of 18, touching their muscles and asking them to squat.
Trevor Parry Jones, prosecuting, said two months later Mr Arobieke approached a 17-year-old in the street in Birkenhead and asked to see his biceps.
When the teenager realised it was "Purple Aki", he ran away "very frightened and very shaken", Mr Parry Jones said.
Speaking from behind a curtain, the teenager said: "As I turned a corner I heard a sound behind me so I turned around and he was there.
"He said he had noticed me around the area and asked me had I been working out.
"He asked me how much I could bench (press)."
The boy told the court that Mr Arobieke then pointed to his arms and asked to see the youngster's biceps.
The boy said: "As soon as I heard that I realised who it was. I backed away and told him I had to go.
"I felt sick and walked away as fast as I could. I went to a friend's house and looked back but he had gone."
The following month the youngster picked out Mr Arobieke in a video identity parade organised by police.
Mark Barlow, defending, told the jury that Mr Arobieke had once been convicted of the manslaughter of Gary Kelly, a distant relative of the victim, but the conviction was later quashed by the Court of Appeal.
Cross-examining the teenager, Mr Barlow said: "Your allegation is a false one, borne out of connection between Gary Kelly and your family and an opportunity to get back at Mr Arobieke."
The trial continues.
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