"Sexual images and videos were sent by both parties. When the complainant stopped replying, Mr Kirby-Parker told her that if she did not start replying he would show the pictures to her brother."
When she told him to leave her alone or she would call the police, he left her a voice message saying she would get what was coming to her and that she only had one warning.
Kirby-Parker pleaded guilty to blackmail and indecent communication with a young person and was sentenced in August this year to two years' imprisonment.
He appealed his sentence last month on the basis that the judge adopted the wrong starting point, imposed excessive uplifts, and should have considered home detention.
The District Court judge adopted a starting point of two years - the same starting point adopted by the sentencing judge for Kirby-Parker's earlier offending.
In the second sentencing, the judge uplifted the starting point by eight months for Kirby-Parker's indecent communications charge, for the fact he offended while on home detention, and for his previous offending.
He then reduced the sentence for Kirby-Parker's early guilty plea.
On appeal, Kirby-Parker argued that uplifts for both the previous offending and for offending while on home detention was excessive.
In her appeal decision, Justice Cull said it was "double counting" for uplifts to be added for those factors when the sentencing judge had already considered it as part of his starting point.
"Those two factors had already been taken into account by the judge, as aggravating factors in setting the starting point of two years' imprisonment," she said.
Justice Cull found this resulted in a "manifestly excessive" sentence.
However she found no issue with the judge's starting point or his decision on home detention.
She quashed the sentence and reimposed one of 19 months in prison, along with special conditions including that Kirby-Parker attend and complete a Child Sex Offender Treatment Programme, and that he not have contact with anyone under 16 except under the supervision of an "Approved Informed Adult" who has been given prior approval by a probation officer.
