The woman stopped working at the pharmacy and returned to Otago University, where she was a student, at the start of 2015.
She and Tiong kept in touch.
However things turned in February 2015 when Tiong discovered she had had a boyfriend the whole time they'd known each other, and told him that she wanted to develop things with the boyfriend instead.
Miller said that to get back at her, Tiong contacted the woman's parents via email saying she'd lied to him about wanting a relationship, and about going to church.
In August 2015, he also Googled the woman's fourth-year pharmacy class list, logged into his old email account at Otago University, where he had also been a student, and found the contact details of her classmates.
He sent a 48-page document attached to an email to her entire class chronicling his interactions with her. At times, he wrote as if he was speaking directly to her, and at other times, about her.
Miller described the emails as "exceedingly intimate and personal".
He wrote, "I'd like to caress her ... stroke hands, legs, hair ...
"I will teach you everything. She asked me pharmacy questions after work ... she always calls me boss and I call her boss ...
"Work undermined our relationship.
"I talked to [the woman] about things in pharmacy as I like the way [she] looks at me with sparkling eyes ..."
One of the woman's classmates described the emails as "extremely inappropriate" and that it "sounds like it was written by a madman", according to the summary of facts read by Miller.
The day after he sent the email, Tiong sent another to the class in an attempt to explain his regret about sending the previous email.
He said, "the idea behind it was to let her know to treat people how you want to be treated".
Miller said the emails were an attempt to embarrass her and portray her as dishonest.
Upon seeing the emails, she contacted police saying she felt frightened of Tiong, and thought he might fly to Dunedin to hurt her, the hearing heard.
Police issued him an official warning, and Otago University's Pharmacy School brought a complaint against him to the Pharmacy Council.
Following the complaints, Tiong had sought counselling to deal with his anger problems.
The tribunal found him guilty of breaching the Health Practitioners Competence Assurance Act 2003 by using his university login and webmail directory for purposes that were not professionally appropriate, and sending unsolicited emails that were unprofessional, in breach of the woman's privacy, and brought the profession of pharmacy into disrepute.
The tribunal censured Tiong, ordered that he must have a professional mentor, could not act as a preceptor for two years, and that he must pay 50 per cent of the Professional Conduct Committee and the tribunal's process costs. They amounted to $11,000.