A schoolboy had sex with a teaching assistant then boasted about their relationship to his friends despite agreeing with her to keep it secret, he has told a court.
Literacy assistant Helen Louise Turnbull, 35, had sex with a 16-year-old on three occasions in her Mini convertible, the prosecution at Teesside Crown Court has said.
The mother-of-two from Haswell, County Durham, has pleaded guilty to one count of sexual activity with a child by a person in a position of trust but denies three other counts.
She has admitted kissing the boy but denied their relationship went further, and said she did not have sex with him or, on two separate occasions, perform sex acts on him.
The court has heard the literacy assistant, who was known at school as Miss Robson, groomed him by giving him sweets and cuddles, then embarked on an affair with him in secret meetings at an industrial estate.
The teenager has claimed that he agreed with Turnbull, known at school as Miss Robson, to keep the affair secret as it would wreck her marriage and career if news got out.
Anne Richardson, defending, asked why he broke the agreement and told friends.
Via a videolink, the teenager replied: "It's lads' craic.
"At the time I was saying one thing to her and when I'm out with the boys, I'm obviously going to be telling them what we have been up to."
The boy said Turnbull also broke the agreement by telling one of her friends what was going on.
He felt "embarrassed and disgusted" with himself and with her when his father found out, he said.
Miss Richardson asked: "How did you feel about the police becoming involved?"
He replied: "The whole situation shouldn't have happened.
"I regretted what happened, because of the effect it had on my life and on Miss Robson's life."
The pupil denied Miss Richardson's suggestion that he was exaggerating what they had done together.
"I have never exaggerated," he said.
"Even if that was the case now, I feel disgusted about what we did."
The trial continues.