"If you can't behave yourself in a backpackers, you should be alone in a hotel room where you can do whatever you like to your heart's content — so long as it's legal," Judge Brandts-Giesen told him.
Williams' lawyer, Paige Noorland, said the defendant was embarrassed and "incredibly remorseful".
He was convicted, fined $500, court costs $130 and ordered to pay $1000 to the victim for emotional harm.