In 1981, a series of murders and one attempted murder occurred in the Shinjuku and Kabukicho areas of Tokyo, targeting women who were strangled inside love hotels at night. The case remains unsolved.
The first known victim, referred to under the pseudonym Hostess A, was last seen alive on March 19, 1981, checking into room 401 of the New El Sky hotel with a young man. She was found strangled the next morning after failing to check out. An ID on her body falsely identified her as a 33-year-old hostess; she was later determined to be a 45-year-old woman who had left her family in 1975 to live in Kabukicho. Authorities speculated she may have worked as a prostitute and that she was picked up from a cabaret job.
The second victim, Hostess B, was strangled with her own pantyhose on the night of April 25, 1981, after being seen entering room 203 of the Coca Palace hotel with a man about an hour earlier. Most of her clothing was missing except for a yukata, and the perpetrator left behind items including her earrings, sandals, cigarettes, and a lighter. She was estimated to be about 20 years old, 157 cm tall, and believed to be Taiwanese. Police released a sketch in an attempt to identify her, without success; investigators believed she may have come from a rural area based on physical evidence from her autopsy.
The third victim, known as Shoujo A ("Girl A"), was last seen alive on June 14, 1981, checking into the Higashioka hotel with a man later described by hotel employees as wearing a suit. Employees, wary because of the earlier murders, checked the room after the man left alone and found the victim bound and strangled with pantyhose; she was still alive but died later in hospital. She was identified as a 17-year-old girl from Kawaguchi city. Coffee found in her stomach during autopsy led investigators to believe she had met her attacker at a coffee shop.
On June 25, 1981, a 30-year-old hostess survived an attack after a man invited her to a love hotel and began strangling her; she fought back, and the attacker fled after stealing her wallet.
Police linked all three murders and the attempted murder to the same unidentified suspect based on similarities including the presence of an orally ingested stimulant in the victims and consistent strangulation methods using pantyhose. The suspect was described as a young, well-dressed man about 160 cm tall, who wore black-rimmed glasses and had a round face in the later incidents; no composite sketch of him was ever released.
The statute of limitations for the three murders expired between March and June 1996, precluding prosecution even if a suspect were later identified. The murders contributed to the adoption of security cameras in love hotels and reinforced Kabukicho's reputation as a dangerous area. In 2016, unfounded rumors spread claiming fires had struck hotels connected to the murders; these were later shown to be false, as the hotels in question had already closed before 2016.