THE heartbroken dad of butchered Brit Lucie Blackman has marked what would have been her 40th birthday by vowing that her killer will never be freed.

Serial rapist Joji Obara was caged for life in 2008 after chopping Lucie's body into eight pieces and encasing her head in concrete.

But he dodged a murder conviction because her remains were too decomposed to work out how she died.

It is feared he could be eligible for parole in Japan in less than two years.

Dad Tim told the Daily Mirror: "He has never taken any responsibility, admitted guilt or shown any contrition.

“If I thought he was going to be eligible for parole at some point I would really seriously look in to doing everything I could to stop it."

Lucy was just 21 when she vanished in July 2000 in Tokyo, where she had been working as a bar hostess.

Her body was found seven months later in a cave near the house of Obara - a millionaire businessman with an obsession with Western girls.

He was jailed for a minimum of 20 years despite not being convicted of murder.

He has already served eighteen years of his sentence - meaning he can apply for parole in 2020.

Every day you think about what she’d be doing now, whether she would be married, whether I’d have grandchildren by her now.

"It leaves a constant chasm of emptiness when you lose someone young like that.”

Tim spends his time running the Lucie Blackman Trust, an organisation supporting the families of Brit murder victims overseas.