A schoolteacher told police that claims she had sex with a teenage pupil in an aeroplane toilet made her “feel sick”.
Eleanor Wilson is accused of having sex with the boy on the way back from a school trip in 2015.
She described the allegations against her as sounding “like a porn film” and said the claims had come from the boy’s imagination, Bristol Crown Court heard.
Ms Wilson, 29, denies four counts of sexual activity with a child under 18 while in a position of trust.
The pupil and the school concerned cannot be identified for legal reasons.
Ms Wilson said during a police interview that having sex with the teenager was “the last thing on my mind”.
“I value my job. I would not have jeopardised going to prison,” she said.
“It just sounds like a porn film. It’s come from his imagination. The other staff there would say that wasn’t happening. It makes me feel sick, the idea of it.”
Ms Wilson, of Dursley, Gloucestershire, admitted meeting up with the boy and texting him after the school trip, explaining “the lines were blurred”.
In police interviews, she said she later told him she was pregnant by her boyfriend Andrew Hall, and was planning to have an abortion because she “felt lonely and upset”.
Ms Wilson agreed she had told the teenager to keep their meetings a secret, but added she only saw him “as a mate”, and did not have feelings for him.
Giving evidence in court for the first time, Ms Wilson said there was “no truth whatsoever” in allegations she had a sexual relationship with a teenage boy, who she described as “quite a charming, cheeky chap”.
She told jurors that during the flight she was regularly checking on several students who were suffering from food poisoning.
Ms Wilson, who now works as a civil servant, said her former boyfriend Mr Hall was “very controlling” and “at times abusive” and by August 2015 she was unhappy with their relationship.
She told the jury she phoned the pupil after an argument she had had with Mr Hall while they were on holiday.
“I called him because I didn’t have anyone else. He knew it was bad and he wouldn’t judge what I said. He knew me,” she said.
The trial continues.