Japanese pop culture and nostalgia is a winning combination. Tamagotchi — a ’90s-era portable digital pet — has returned with a vengeance, with an accumulated number of shipments from its debut in 1996 through last month topping 100 million worldwide.

Since the first Tamagotchi hit stores, parent company Bandai Namco Holdings has released updated models, but the growth of the valuable “kidult” market — a multibillion-dollar segment that encompasses teens and adults — has given it a second wind.

Tamagotchi is one of several examples of ’90s games making a comeback among adults, with toy analysts citing the power of nostalgia to invoke escapism.

“The current Tamagotchi boom is not limited to Japan, but also captures the ‘nostalgic demand’ of those who experienced the first Tamagotchi boom overseas,” Bandai said in a media statement. “Two generations — the child and the parents — are both enjoying it.”

For Gen Z consumers, the toys were attractive as a fashion accessory, the company said.

In July, Bandai Namco released “Tamagotchi Paradise,” the company’s 37th iteration of its popular portable with a price tag of ¥6,380, or $44.99 in the U.S. The latest digital toy enables users to connect with each other, allowing pets to battle or procreate.

The international market is also an important driver of Tamagotchi’s success. Japan makes up 49% of buyers, but the U.S. represents 33% of demand, while Europe is 16%. Asia, excluding Japan, is just 2%.

Last year, the company launched a physical store in the U.K. as global sales buoyed overseas growth. It also has stores in New York, New Jersey and Madrid.

When the first Tamagotchi was released in Japan in 1996, Akihiro Yokoi, one of the inventors of the toy, said he dreamed up the concept of a digital pet after seeing an advertisement in which a boy was upset that he wasn’t able to take his pet turtle along on a holiday.

Alongside colleague Aki Maita, he developed the product into its recognizable egg-shaped form. Maita has said Tamagotchi became popular because "humans ... find joy caring for something."

Collectable, portable, and affordable are among the factors that made Tamagotchi a winning business proposition from the get-go. The name is a portmanteau of tamago, the Japanese word for egg, and wocchi, for watch.

The game, in which players care for a demanding virtual pet as it matures, was an instant hit domestically, and when the company expanded overseas in 1997, it generated a global craze.

Tamagotchi sold 10 million units in the first eight months following its release, becoming a household name in the process. But the fad soon shrank, with the company suffering from excessive inventory, which saw it incur financial losses and ultimately restructure.

But it saw a bump in sales in subsequent versions over the past three decades. In 2004, a new Tamagotchi version, which allows users to communicate with each other with infrared communications, sold 5 million products in the first year.

A 2018 version of the virtual pet device, “Original Tamagotchi,” teamed up with popular fashion brands, selling 11.52 million devices as of the end of July.