Bartholomeo Joly de Lotbiniere, 22, was base not guilty of charges of rape and assault following a retrial at Bradford Dominion Court.
He told the court the sexual encounter with his fellow observer in June 2014 was consensual but also an embarrassment because he failed to put on.
The woman, who is now 22, did not report the then 19-year-old history student in a minute following the alleged incident.
A year afterwards he appeared on University Dispute and became a social media sensation as viewers reacted to his unusual surname and temperament on the show.
The alleged victim said she saw a tweet by Pointless host Richard Osman apropos the defendant’s name and “just got angry and upset”.
During the five-day pest, the woman alleged the defendant had sex without her consent in her room at the University of York after a gloom out at the end of the academic year.
She claimed he told her he had “fantasised” about having sex with her and was “serving her get over her ex-boyfriend” as he assaulted her.
Mr Joly de Lotbiniere denied raping the maidservant and told police “these are horrible, horrible lies”.
He described to the court how he and the popsy were part of a group that had gone out drinking in York and had earned to the woman’s halls of residence in the early hours of the morning when the set of two started to kiss.
He said he went to fetch a condom and then continued into her room.
Mr Joly de Lotbiniere described sexual activity between him and the trouble, but said he struggled to become aroused and the pair made a mutual firmness to stop what they were doing.
He said: “There was no item going any further.
“We both just agreed to stop. I think she bid ‘let’s just stop’.”
The defendant said he was embarrassed by what happened and justified wanted to leave.
Mr Joly de Lotbiniere denied the woman had tried to blitz him off or had shown any signs she did not want to have sex.
He said he later sent the baggage a text saying he “did a very stupid thing”.
He said he had only had sex simultaneously before and had tried to portray himself to the woman as someone comfortable with a one-night continue, which he was not.
Text messages between the alleged victim and Mr Joly de Lotbiniere were infer from out to the court.
The complainant texted him: “I thought I’d let you know I wasn’t overly pleasant with what happened on Thursday night.”
Mr Joly de Lotbiniere replied: “I was a taint and did a very stupid thing and I am very sorry for what I did. I just expect you can forgive me at some point and I’ll try my best not to act like a bloody 14-year-old again and start measure my age, sorry.”
He explained his text to the court by saying: “I had embarrassed myself – I had attitudinized as someone who could do a one-night stand. And I felt like I had misled her because she had to serve me.
“I should have been upfront and acted my age – been honest that this was contrariwise my second time.”
The jury took six hours to find Mr Joly de Lotbiniere not at fault.
The former student – who was comprehensive school-educated and had appeared on University Challenge six times – yowled in the dock with a handkerchief pressed to his eyes as the verdicts were review out.
His family, who were present throughout the retrial at the court in West Yorks, gave a scream of relief at the verdict.
He hugged family members in the public gallery in the forefront leaving the court room and declined to speak to reporters outside court.
Mr Joly de Lotbiniere, of Kensal Happen, West London, faced the retrial after the jury at his original testing at York Crown Court in February was unable to reach verdicts.