The father of a British teacher found dead in Japan in a bath filled with sand has said he "will not rest" until her killer is caught.
Lindsay Ann Hawker, 22, of Brandon, Warwickshire, was discovered on an apartment balcony in Tokyo.
Bill Hawker, who is in Tokyo, said: "My daughter was a lovely girl, she would have helped anybody."
Japanese police say the post-mortem suggests Miss Hawker was strangled or asphyxiated. A suspect has been named.
He is 28-year-old Tatsuya Ichihashi, who lived at the flat. A warrant has been issued for his arrest.
Miss Hawker also suffered severe injuries to her face and arms.
Her father and her long-term boyfriend Ryan Garside are in Tokyo to formally identify her body.
Mr Hawker told a press conference his daughter had researched Japan thoroughly before taking up work as an English teacher, to make sure she knew the dangers.
He also insisted she had not been in a relationship with Mr Ichihashi.
"I believe my daughter was tricked into going to this man's apartment under the pretext of giving English lessons," he said.
"It was because she would help anybody, she is where she is now. My daughter didn't come here to be murdered... she came here to teach."
Mr Hawker said he thought Mr Ichihashi was a loner and a "social misfit" and insisted: "I will not rest until the suspect is caught."
Mr Garside told the press conference he had been with Miss Hawker for four years.
"She was the best thing in my life," he said.
"I loved her so, so much. We planned to one day get married and start a family.
"That man has ruined mine and Lindsay's plan - he ruined our dream."
Miss Hawker graduated last year from Leeds University and had been teaching English at Koiwa school in Tokyo.
She was reported missing by her flatmates on Monday afternoon after disappearing from her home on Sunday.
The suspect fled barefoot when police arrived at his apartment
It is believed she had gone to Mr Ichihashi's apartment for the first time on Saturday, to give English lessons to him.
She had left details of the address at home.
Miss Hawker's sister Lisa, 25, said in a statement that her sister had felt safer in Japan than in the UK.
"Thousands of young people go abroad each year and for some reason the dangers of home seem to be forgotten," she said.
"If Lindsay's death can make at least one young person abroad be more vigilant then perhaps one more family can be spared the pain, the devastation, and the despair we are all experiencing."
Younger sister Louise, 20, said the family had been "torn apart" by what had happened.
"You never think a thing like this could happen to you. We are normal people, and it does, and it hurts more than you can imagine," she said.
Local police said a handbag and passport thought to belong to Miss Hawker were found near her body.
Superintendent Yoshihiro Sugita, from Chiba Prefectural Police, said: "We have found no traces of blood and there was no sign of a physical struggle.
"The victim was completely naked and her clothes were around the apartment, although we don't know whether they were taken off by her or by the suspect."
Miss Hawker kept in touch with her boyfriend via the website Facebook and in one of her last entries on 20 March, she spoke of a man following her home.