A 75-year-old former headmaster is on trial over allegations he had sex with a boy he met through a Christian youth group.
John Coatman, now retired, is in the dock at the Old Bailey charged with buggery and two counts of gross indecency with a 14-year-old boy over a 12-month period in the 1970s.
The allegations cover the time when Coatman was headteacher of St Andrew's Church of England secondary school in Croyden and involved in the Christian group for boys. Prosecutor Corrine Bramwell told the court how "rough and tumble" turned sexual.
She said: "[The complainant] recalls John Coatman asked him whether he's ever ejaculated before, and he spoke to him about sexually transmitted diseases.
"He describes that during the contact both of them were naked and accepts that he was excited by the attention given to him."
Sexual contact took place on four or five occasions, said Bramwell, and escalated to anal sex once.
Coatman, who was given an MBE in 2012, denies the charges.
The victim, who cannot be named for legal reasons, did not report the incident to police until 2014 despite not being "entirely comfortable" with what happened.
He said he had been bullied before joining the Christian group which gave him a "sense of a home" away from family. But he wept as he told an officer in a taped police interview played to the court: "It was my first sexual experience. I think it probably has coloured a lot of my sense of selfworth since then."
The trial continues.
