Serial killer Takahiro Shiraishi's expressed desire to be executed quickly moved a step closer Jan. 5 as his death sentence was finalized following the expiry of the deadline to file an appeal.

Shiraishi, 30, was sentenced to death by the Tokyo District Court’s Tachikawa branch on Dec. 15 for killing nine people aged 15 to 26 at his apartment in Kanagawa Prefecture in 2017. Many of his victims, eight of them women, had been raped and robbed.

Shiraishi dismembered the bodies and stashed parts in coolers and tool boxes.

The defendant approached the victims, most of whom had harbored desire for suicide, via social media sites, according to court testimony.

In dismissing arguments by his defense team, the court ruled that he murdered the victims without their consent.

After the court ruling, his lawyers appealed the death sentence to the Tokyo High Court, arguing that their client is guilty of the lesser charge of murder with consent. They also called for a reassessment of his mental capability to be held responsible for the slayings.

Shiraishi submitted a document to retract the appeal several days later.

During his trial, Shiraishi expressed a desire to be executed quickly as a way to atone for his crimes and lessen the pain faced by grieving families of the victims. 

Executions in Japan are carried out by hanging.