Five days later, the victim offered Kerr $120 not to contact him again.
She agreed and the money was transferred.
But Kerr then demanded $200 from him and threatened to go to the police and make a rape allegation against him unless it was paid.
She also said she would spread all around town and on social media that he was a convicted sex offender and that he preyed on young girls.
The victim, who has no convictions for sexual offending, contacted police.
Kerr would later tell police it was a "joke" and that she was not going to follow through on the threats.
In sentencing Kerr on May 8, Judge Richard Russell noted that he must sentence her on the basis of the least restrictive outcome, having adopted a starting point of 15 months' imprisonment.
However, he added that the sentencing purposes and principles of denouncing her conduct, and to deter both her and others, meant she must receive a custodial sentence.
The judge found the occupants at a proposed home detention address meant such a sentence was inappropriate.
Defence counsel Rennie Gould argued that Judge Russell erred in imposing a jail term.
She claimed that it was a low-level blackmail offence involving a small amount of money and that imprisonment was an "unusual response" to the crime.
However, in a new ruling, the Court of Appeal found that Kerr's sentence of 12 months' jail to be "entirely appropriate" and dismissed the appeal.
The appeal judges found the threat of a rape allegation was "extremely serious".
They also said Judge Russell was right to take into account Kerr's previous dishonesty convictions and that her offending had occurred while subject to an intensive supervision sentence.
