Junko Furuta was a 17-year-old Japanese high school student who was abducted, tortured, raped, and murdered in the late 1980s. Her murder case was named concrete-encased high school girl murder case due to her severely mutilated body being discovered in a concrete drum filled with 208 litres of concrete. The murder was mainly perpetrated by four teenage boys, Hiroshi Miyano, Jō Ogura, Shinji Minato, Yasushi Watanabe, who were known deliquents and serial rapists.

About 100 people knew about Junko's captivity, but either did nothing about it or themselves participated in the torture and murder. Most of the participants were friends of the teenage boys, who were low-ranking members of the Yakuza.

Junko was held captive for 40 days, during which time she was repeatedly raped, beaten and tortured. According to their trial statements, the four of them:

Raped her over 400 times. They also invited and encouraged their friends to humiliate and gang rape her.
Starved her.
Beat her several times with golf clubs, bamboo sticks and iron rods.
Used her as a "punching bag" by hanging her body from the ceiling.
Dropped barbells onto her stomach several times.
Forced her to eat live cockroaches and drink her own urine.
Forced her to masturbate in front of them.
Inserted foreign objects, such as iron bars, scissors and skewers into her vagina and anus, rendering her unable to defecate and urinate properly.
Shoved a still-lit light bulb into her vagina.
Set fireworks into her anus, vagina, mouth and ears.
Burnt her vagina and clitoris with cigarettes and lighters.
Burnt her eyelids with hot wax and lighters
Tore off her left nipple with pliers.
Pierced her breasts with sewing needles.

Furuta was held captive in the house of one of the abductors. His parents knew and did not intervene, even as she begged for help, begged to be killed to end her suffering.

The accused were convicted as Young offender, received light sentences, and are now free.