Halloween celebrations in Japan have become famous around the world for being a night of debaucherous cosplay, with young people congregating in city hot spots and theme parks to snap selfies in outrageous outfits and ghoulish get-ups.
In recent years, a giant street party has drawn people dressed in uber-graphic costumes like sexy zombies, stabbing victims or as the eccentric animal skin-clad viral star Pikotaro to Shibuya's famous scramble crossing, making movement nearly impossible as thousands of revelers mingle in a heaving mass.
"From about four years ago, people started going out on the streets rather than enjoying Halloween events in clubs or bars," Shibuya Ward Mayor Ken Hasebe said at a recent press conference ahead of the annual celebration on Oct. 31.
But where did all the wicked wackiness get started?
According to locals, the history of Halloween in Japan can be traced back to the 1970s, when a bookstore in the nearby pop-culture hub of Harajuku began selling Halloween paraphernalia and organizing costume parades for the first time.
"How we absorbed Halloween culture reflects postwar history in Japan," a spokeswoman for toy and bookstore operator KIDDY LAND Co., said.
In 1950, the store's predecessor -- Hashidate Shoten -- opened in Harajuku, where many facilities were built for U.S. military personnel after World War II. To meet demand, the store started to sell foreign books and high-quality Japanese toys.
Foreign customers who lived in the area began asking about how they could get their hands on Halloween items.
"The staff at the time were asked by foreign customers why we don't carry Halloween stuff," she said.
Staff members from the store traveled to the United States to learn about the Halloween tradition and later started hosting children's costume parades in front of the store around 1983.
The event, which saw about 100 participants at the start and attracted more and more people each year, spread from foreign customers to Japanese.
With the help of Tokyo Disneyland introducing Halloween events in 1997, the day is now widely known for providing an opportunity to dress up and party throughout the nation, she said.
The media, which showed footage of youngsters exchanging high-fives and having fun at the scramble crossing in Shibuya during the 2002 FIFA World Cup, played a big role in the district becoming party central for Halloween, Hasebe said.
Hasebe, who is the first mayor to hold a press conference to address the wild Halloween celebrations, called for a concerted effort to "get people to go home by the last train and keep the noise level down after midnight."
About 70,000 people visited the district on Halloween in 2015 but the numbers have been swelling ever since, according to the Shibuya Ward office. Last year, half of the crowd wore costumes while the other half was there to mingle and enjoy themselves, he said.
According to the office, there was about 7.8 tons of garbage collected last year, including bottles, cans and costume detritus.
The streets were strewn with glass from broken bottles and restrooms in the area's shopping district were left covered in makeup, fake blood and other substances only required on Halloween after being overrun by people using them to change into their outfits.
This year, the ward office is asking 17 retail stores around the scramble crossing to stop all alcohol sales in bottles.
"I'm sure the celebration can be carried out in a good and moral spirit. I want to avoid regulating things if at all possible," the mayor said. "(Halloween) is beginning to take root in the culture of Shibuya. I want to foster it."
In the past, several people, but still a tiny number considering the massive crowd, were arrested on suspicion of stealing or groping women in the crowd, according to police.
The Metropolitan Police Department has also taken measures in recent years to prevent accidents, such as deploying its so-called "DJ cops," officers who marshal the crowd with a spirit of goodwill, rather than issuing stern orders.
Just as Japanese soccer fans gained a reputation for cleaning up stadiums during the World Cup in Russia, many volunteers have been involved in tidying the Shibuya streets before and after Halloween.
A committee, comprised of businesses and the Shibuya Ward office, supported volunteers for the past three years by offering them pumpkin-shaped orange garbage bags and lending out work gloves and tongs.
Other than setting up temporary waste collection centers, the committee will install boxes where people can discard their costumes and other unwanted items. The leftovers will be sold online, with proceeds to go toward future cleanup activities in Shibuya.
"I hope this new attempt will encourage people to be conscious of reusing, rather than throwing things away," a member of the committee said.