In handing down the ruling, the judge referred to evidence submitted by prosecutors including a diary kept by Obara, video tapes showing him raping women and writing in which he boasted, "My goal is to have sex with 500 women by the time I am 30".
Memories of the Blackman case were revived in March this year when Briton Lindsay Ann Hawker, a 22-year-old English teacher from Brandon near Coventry, was found dead in a sand-filled bathtub in an apartment near Tokyo.
Police found her remains – including a severed head encased in concrete – seven months later in a cave by the sea 250 metres from Obara's condominium.
Obara had told the court that he had drinks and watched videos with Blackman in his room that night, but that she was fine when he left her the next day.
Last September, Tim Blackman accepted a 100 million yen "condolence payment" from a friend of Obara, saying he would donate a substantial amount of it to a charity set up in his daughter's name.
Foreign hostesses from a range of countries work in Tokyo, but many work illegally on tourist visas, making it difficult for them to report problems to police.
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