He added: “You probably thought it was laddish behaviour at the time. In truth it was foul sexism. It demeaned women and trivialised rape – a word you personally threw around lightly.
“Only now do you realise how serious rape is.”
The judge said: “That night, Joe Clarke did nothing wrong – nor did she. You were definitely playing the sexist game that evening, making a nuisance of yourself at the bar.
“But you went home alone, drunk and frustrated. I have no doubt at that stage you planned to go to bed on the mattress at Joe Clarke’s.
“When you realised a sleeping woman was there, you saw a chance, climbed onto the mattress, rousing her.”
The woman told the court the first thing she remembered was waking, already unwittingly engaged in a sexual act.
His barrister, Michelle Heeley QC, said her client had expressed remorse.
In what the judge called a “brave” victim impact statement, the woman Hepburn attacked described her ordeal as “evil” and a “heinous crime”.
Judge Tindal praised her for giving evidence through two trials, adding: “I hope she can now finally be able to look to her future which will be, I am sure, bright.”