Maeue was born on August 8, 1968 in Osaka. He had a paraphilia, documented in the psychiatric evidence at his trial, in which he was aroused by watching a person choke or struggle for breath; he had a record of assaults on that pattern going back years.
In 2005 he used Japanese internet suicide-pact boards, which were then widely used and were the subject of national concern after a series of group suicides, to find people who wanted to die. He arranged to meet them, promised to die with them, and strangled them: a fourteen-year-old boy in February 2005, Michiko Nagamoto, twenty-five, in May, and a twenty-one-year-old male student in June.
He was arrested on August 5, 2005 and confessed. He was convicted and sentenced to death, and he did not appeal.
He was hanged at Osaka on July 28, 2009.
The case changed how suicide-pact sites were regarded in Japan and prompted police guidance to providers about them. What makes it distinct is the method of approach: the victims came to him voluntarily, believing they were going to die together, and that belief was the instrument.