The boy's mother and other family were in court to watch the sentencing.
Crown prosecutor Jo Woodcock said the Crown didn't accept that the man should be given a discount off his sentence for his show of remorse, his pre-sentence report writer having noted he continued to justify and minimise his offending.
She also pointed out that there was no independent material in front of the court to show he was of good character.
The man's counsel, Mark Bullock, said the man suffered from depression at the time of offending and wasn't dealing with it. When he said he was "intrigued", he was trying to explain, not trying to minimise or justify his offending.
He was disgusted with himself and he didn't know how he got into the situation, or why he was intrigued by the boy, Mr Bullock said. No inducements or threats were made to the boy and the man accepted responsibility by telling police and pleading guilty.
He was willing to engage in programmes and didn't know what more he could do to show he was taking responsibility, Mr Bullock said.
Judge Cameron said the man had prior convictions, but they were historic and not related to sexual offending.
His pre-sentence report writer noted that he tried to justify his offending by stating it was his "duty" to teach the boy the correct sexual activities.
He was deemed at moderate risk of reoffending.
He had sent a letter of remorse to the victim's mother, and her victim impact statement indicated the whole family had been hurt and betrayed by his actions.