Gisborne teenager Reiha McLelland told her teacher she needed him to "save her" but he says he didn't let school professionals know because she "bounced back".
And despite receiving 632 pages of texts and emails from Reiha, when police asked Sam Back what he knew about her emotional state he told them she never opened up to him.
Under cross-examination during the inquest into Reiha's death, held in Gisborne, a one-and-a-half page email from the 13-year-old was put to the former intermediate teacher.
It was sent in November and detailed her troubles, state of loneliness and emotions. At one point she said "right now I'm the farthest point from being okay".
The teenager also sent Back a poem in which she said 99 per cent of her wanted to die, but the other one per cent was afraid of what she'd miss when she was gone.
"I need you to save me."
Adam Holloway, acting for a mental health professional whose name is suppressed, asked whether Back read this at the time this as a cry for help.
He said he "sort of read it in that way" but also didn't take it too seriously because Reiha "bounces back" and ended the email with "I'll see you at school tomorrow".
He told police during their investigation which did not lead to charges, that "she never at any stage opened up to me" but said in the inquest today: "I suppose I should have seen it that way."
And in all the thousands of texts and emails the pair exchanged, Holloway said he could not find evidence that the former teacher urged the teenager to speak to professionals.
"That's the one thing you only ever said in words," the lawyer said.
But Back told the court it was something they discussed often in person - especially her seeking help when she got to boarding school in Napier.
Coroner Carla na Ngara questioned why he was able to recall one phone conversation with Bruce McLelland so clearly yet so many other facts - such as how many nights Reiha stayed at his home - were beyond recollection.
It's accepted there were seven to 10 sleepovers and on at least two of those evenings, Back's partner was out of town.
"Is that because it happened so often, that she was coming to stay?" na Nagara asked.
"No. I think it's very difficult because there are things which stick out ... and there are things that you just kind of let go," Back said.
The coroner put it to the ex-teacher whether it would be a fair interpretation of the evidence presented so far that the intensity of the pair's "unique friendship" - as Reiha called it - and the pressures she felt she was under to keep it quiet was a significant factor in the context of her death.
"Yes ... But the things Reiha was sharing with me were limited and although in hindsight carried more weight than I perceived them at the time ... I don't think it was as secretive as it appears to be."
Na Ngara said it was for the inquest to establish what impact the "unique friendship" between a man in his 40s and a 13-year-old girl had on her and asked Back to put his personal rational aside.
In the days before Reiha's death, where she is presumed to have taken her own life, phone records show she got calls from a blocked number - the same week Back was told he'd been found guilty of serious misconduct by the Teacher's Council and voluntarily stood down from Gisborne Intermediate.
Holloway asked him whether he or Mepham had made those calls or told Reiha about the disciplinary process.
"Never," he said.
Back's lawyer Adam Simperingham submitted the teacher wasn't a wedge between Reiha, her family and mental health professionals as counsel representing other bodies had said.
In fact, there was a lot of evidence showing how the former teacher urged Reiha to open up to her parents and seek help when she got to Napier Girls High School.
However, he accepted he should have called Bruce McLelland - who he called "Brucie" - about his daughter's troubles but said he thought he was acting in her best interests.
Back's partner, Angie Mepham, said she was unaware of the extent of the communications between him and the teenager. He told her it was because she was very ill and he didn't want to add to her stress.
The inquest has been adjourned until later this month when Mepham will be questioned before the pair travel to Canada.
Where to get help
• Lifeline: 0800 543 354 (available 24/7)
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