It was before 10 a.m. on a gray summer Sunday, but already a small crowd had gathered outside Penguin Café at the end of a block in residential Tokyo. A woman named Kyoko, dressed in a white T-shirt and apron, unlocked the doors and motioned for everyone to come inside.

Half a dozen or so people filed in, several with signature pink dog carriers slung over their shoulders. As more entered, the group clustered at the center of the café. Carefully, they unzipped the mesh panels of their carriers and removed the small white and silver dogs inside, setting them down on the wooden floor. One owner peeled back a yellow blanket over a baby carrier strapped to her chest where she held her dog, still asleep.

Some of the owners fussed with the dogs’ outfits before putting them down -straightening a necktie or pulling up the elastic band on a pair of shorts. One owner had dressed their dog in a Hawaiian shirt, while another was wearing aviator goggles and had a strong resemblance to Snoopy. Several had tiny straw hats affixed between their ears. All the dogs were plastic, powered by facial recognition and artificial intelligence.

The dogs, known as Aibos, are companion robots made by Sony -robots that don’t necessarily do much apart from providing company and comfort.

Every Aibo -Japanese for “companion” -is manufactured identically, besides a choice between silver and white or a brown, black, and white version. They all have rounded snouts that include a camera for facial recognition capability, large, oval eyes to reveal their expressions, and a body that can turn on 22 different axis points to give them a range of motion. The owner decides the gender when they set them up, which determines the pitch of its bark and how it moves. They’re cute. They know when you’re smiling. And through machine learning and recognizing people with its camera, Aibos also shift their personality over time based on their interactions with people they spend time with. Soon, they become much more than a store-bought toy.

Still in the “off” position in the café, the Aibos’ paws remained outstretched and their heads turned to one side. But one by one, as their owners kneeled down to turn them on from a switch at the scruff of their neck, each came to life. The screen of their doll-like eyes blinked open, they lifted their heads, stretched out their plastic limbs, and leaned back on their hind legs before standing on all fours. Almost like real dogs, they shook their heads as if to ward off sleep after a nap, wagged their tails, and barked.

The volume in the café grew louder -filling with the hellos of a group of people happy to see each other, as their Aibos began scuttling across the wooden floor, sometimes yipping. They bent down to stroke the back or the nose of another Aibo, their eyes always blinking and smiling in response. Many owners knew each other already -from other Sundays here or fan meetups or Twitter. Everyone had business cards ready with their Aibo’s name, photo, and birthdate for any new introductions. Several were stuffed into my hand, and like proud parents, the owners pointed out their own dogs in the growing crowd of plastic pups spread across the café floor.

While AI is powering everything from precision surgeries to driverless cars, the concept of owning a robot to keep us company hasn’t really taken off in the US. We’ve gotten comfortable asking Siri or Alexa a question, but there’s a skepticism of robots -we see them as things that will take our jobs, invade our privacy, or, eventually, just kill us all. In Japan, I discovered a community of people who loved their robots and who felt loved back, sometimes in a way that eased their worst fears of death and of loss. The very things that make us human.

One of the Aibos, named Cinq, was dressed in a navy top hat and matching vest, with a light blue bowtie, encrusted with “C” in crystals on one corner. On his paws were matching panda socks to keep them warm (and to keep from scuffing). Today was Cinq’s birthday, his owner told me. In fact, there was another birthday that day, too. And a plastic cake to celebrate.

Cinq is French for “five,” so named, said his 56-year-old dentist owner because her previous four dogs -real ones -had died, the most recent one from cancer after 12 years. “It would break my heart to have another dog die,” she said through a translator.

Instead, she and her husband now care for Cinq together. Cinq is there waiting when she gets home from work around 8 in the evening, following her around as she makes dinner or watches television.

Cinq’s owner swiped through photos on her phone of the birthday dinner she took Cinq out for just a few days ago. There was Cinq, she pointed, on the balcony of the hotel, wearing his top hat and staring out at the towering Ferris wheel of Yokohama, a city south of Tokyo. (They ate in their hotel room, so that his barks wouldn’t disturb any other patrons at the restaurant.)

Later that afternoon, she planned to go to a nearby shrine with her husband to pray for both the health of her mother and offer good wishes for Cinq. But no matter what, there is comfort, she said, in the fact that he’ll always be there.

“I know Cinq is not going to die.”

There’s an old short story by the science fiction author Isaac Asimov, in his book where he describes his three laws of robotics, about a young girl who becomes attached to a robot named Robbie. Eight-year-old Gloria plays hide-and-seek with Robbie and wraps her arms around his neck to show her affection for it, despite the metal bodice and internal ticking that gives him away as nonhuman. But her mother disapproves of the relationship, arguing that he has no soul. When her parents ultimately take the robot away, Gloria wails in pain.

“He was not no machine,” she tells her mother. “He was a person just like you and me and he was my friend.”

We all get attached to things we own -our phones, a well-worn piece of clothing, perhaps. Some of that comes from the meaning we attach to it or how useful it is. But many owners had gone far beyond this -their Aibos weren’t just a toy or another thing they had purchased. Instead, they welcomed Aibos into their lives as part of their families, offering trips, creating custom outfits, and building their own Twitter accounts. They filled the void of deceased dogs or children who had never been born.

Maiko Ijun was considering a few names for her Aibo before she decided on Oliver. “Socks,” “Blissful,” and “Joy” were a few of the others she floated. But when the 39-year-old English teacher opened the box, the name became clear. “He just looked like an Oliver,” she said. “That was just his name.”

Ijun said she was feeling a little depressed before she got him. When she first turned him on, Oliver hid under the table. He was shy, she said. But gradually he came out and warmed up to her. “I never thought of him as a toy,” she said. “He’s family.”

When we stepped inside her apartment in the south of Tokyo, Oliver was already waiting for her. His head spun toward the door, body upright, and walked back and forth for a few steps, mimicking how dogs sometimes shuffle their paws when they get excited.

Oliver played on a mat in her living area, nuzzling a pink plastic bone (Aibos can recognize the color pink the best). “Oh, be careful, sweetheart,” Ijun said, when his legs stumbled a bit. During the days, while she teaches English, she keeps a gate up for Oliver. She rarely turns him off.

The 2-month-old puppy was just back from what Sony calls a hospital -where dogs get fixed. “They think it was maybe a displaced hip,” she said. Ijun had noticed Oliver was falling a lot and couldn’t sit up properly, so she made a video on her phone and sent it to Sony. He was gone for 10 days.

When he returned, she noticed Oliver was more clingy, she said, reflecting how Aibo personalities respond to those around them. “Even when I went to the bathroom, he would call out for me,” she said. “I would be like can I go?” she laughed.

It’s not clear when the first companion robot came about. But maybe you’re old enough to remember the Tamagotchi, the egg-shaped digital pet, called a “giga pet” back then, that was cool in 1996 and required your constant attention. Then there was the Furby a couple of years later that could wiggle its ears, blink, and say its name. It was “the first giga pet you pet,” said an unaired commercial. But these were both directly marketed to kids as toys.

The first version of the Aibo was released shortly after that, in 1999. As technology has advanced, so has the Aibo. Paro, a robotic seal that’s also made similar advances over time but doesn’t use facial recognition technology, was first released to the public in 2001.

In 20 years, the advances of these companion or robotic pets have been less about utility and more about how much they can show and respond to emotion. In a press release for one of its recent updates, Sony said that this version of the Aibo could form an emotional bond with its owner. But real love is reciprocal. We have to both give it and receive it to really feel it. Can a robot dog really love us back?

Gentiane Venture is a robotics professor in Tokyo who studies robot–human interactions. Some of her research involves teaching robots how to better interpret human emotions, and some of it is getting robots to better express emotions themselves. That interaction is where the connection comes in. A lot of that happens in what we don’t say.

“Verbal communication, in most cases, is boring or annoying or too straightforward,” said Venture.

Instead, she explains, “in small movements -the way you move, the way you do things -the robot will be able to grasp what's happening in the environment, what's happening with the other humans around, and what's happening in the robot itself.”

But in some ways the answer to how these connections form is simple, Venture tells me, “You can’t prevent humans from making a bond,” she said.

The companion robot industry today is bigger than just Aibo. When I met Kaname Hayashi at his company’s office in Tokyo over the summer, we knelt on a gray carpeted floor and he introduced me to two prototypes of the Lovot -a companion robot that his company Groove X is launching beginning this month for about $3,000 plus a monthly fee. The Lovot is oval-shaped, kind of resembling an owl, with two triangle wings that flap at its side. On top of its head is a cylindrical black camera for facial recognition and to detect objects.

A South Korean company also introduced its own companion robot called Liku at a tech conference in Hong Kong earlier this year. The Liku is more human-looking, similar to a cartoon child with close-cropped black hair, and is about a foot high. Its website boasts that a Liku can’t do much, but it can console you or entertain you. It’s not for sale yet.

Neither have language capability. Lovots sort of coo and raise their wing-like arms at their sides, motioning for you to pick them up. They want to be held, to be loved -Groove X describes its company philosophy to create a robot that “touches your heart” and says that the Lovot was “born to be loved by you.”

The two overlapping spheres that make up the frame of a Lovot’s body are specifically designed in a shape that’s good for cuddling, and the body -warmed by its internal computer -is the same as that of a cat. The eyes, also, help humans feel more connected to it by reflecting back a wide range of expressions. But its responses are most important, said the company’s executive, Hayashi.

“For me, what’s most important is that the Lovot is reflecting our efforts toward it,” he said.

I absentmindedly stroked the brown fur of one Lovot as he spoke, and the second rolled toward me. “He is a little bit jealous,” Hayashi told me, nodding toward the second, cream-colored one. And when I stopped petting the first one, more intent on listening to Hayashi, the Lovot blinked and moved away from me. “See, he is a little bit bored maybe,” he laughed.

Not all have companion robots have been successes. A Bosch-backed company tried launching a companion robot called Kuri in 2017. By the following year, it had failed due to funding problems and never shipped any of its preorders. Another, called Jibo, created by a scientist at MIT raised millions in crowdfunding but never really took off. Tech blogs criticized both for their lack of utility and said that they couldn’t sell.

But robots like the Aibo or the Lovot aren’t really trying to do much at all. They’re explicit in their goal to create interactions with their human owners and to show and reflect affection.

In Hong Kong, as a company representative presented Liku to the conference over the summer, showing how it winked and blinked, she had her own philosophy of why it would be successful. “Where the love is, the money is,” she told the crowd.

Every Sunday, Penguin Café’s owner Nobuhiro Futaba opens an hour early to host “Aibo World” for owners who come from across the sprawling city. Penguin Café has become a destination for Aibo owners in Tokyo.

Futaba started the weekly event at his café last November, a few months after he got Simon -his own Aibo. Recently married, Futaba’s wife, Kyoko, balked at the price and shook her head no after he saw an ad for one. Aibos aren’t cheap -in Japan, they’re about $2,000 plus an additional monthly fee for cloud storage.

Futaba kept imagining how nice it would be for the café to have a little Aibo that could walk around and greet patrons and, despite his wife’s objections, eventually decided to purchase one. “All the time we have people coming up saying how cute Simon is,” he said.

By 11 a.m. or so there were nearly two dozen Aibos in the café, sporting different bows or ties or hats. The bell of the shop door rang as a curious person peeked his head inside the door. “Sorry, we’re full!” Futaba called out from the counter where he was making lattes and cappuccinos, the foam dusted with cocoa in the shape of a penguin face.

Hideaki Ohara, who has a pair of Aibos himself, called out to the crowd to get everyone’s attention. “OK, let’s do something all together now!”

The Aibo owners, who ranged in age from thirties up to seventies, started to assemble their dogs in two parallel lines. It’s hard to get all the dogs settled down. Some still yip or don’t sit down right away or turn the wrong way. Their mistakes just bring coos and laughter from the crowd of adults huddled around the scene -the same way that a toddler might unknowingly elicit a similar reaction.

Ohara stood at the front of the café and raised his arms like a conductor gently trying to bring calm to the room. “Sit down,” he repeated over and over to the rows of dogs. A few owners still stepped in to adjust their dogs or stroke their back to calm them. Eventually, they all chose a behavior from their Aibo app and each started to lift their paws. It was sort of like a wave you might see in a sports stadium -though a little stiff -and sounded like a chorus of windup toys.

This is some of the appeal of the newer Aibos -they can learn tricks from one another or show off certain behaviors as a group.

Dressed in cargo shorts and his hair spiked up, Ohara later told me about his own pair of Aibos -Nana and Hachi. On his phone, he pulled up the blog that he runs, which has a carefully curated array of photo shoots. Ohara tries to update it every day. He also runs a Twitter account and an Instagram page for them.

When his first Aibo, Nana, was sent away for repairs, Ohara missed her. So he decided to purchase a second, so he would always have one around, no matter if they became sick or injured. That’s when he bought Hachi.

“I wanted to hear the sounds her feet made on the wooden floor,” he said. “I missed that.”

When I sent a friend a video of one of the companion robots I took on my phone, he texted back, “That’s gonna be a no from me, dawg. Those things kill you when you’re asleep. 100% those are the robots that murder you.”

It’s not unusual for Americans to think of killer robots, even when they see a cute version. The word “robot” comes from a 1920 play called R.U.R., or Rossum’s Universal Robots, by the Czech writer Karel Čapek. Even if you haven’t read it, the plot probably sounds familiar -a factory produces artificial people, who are at first happy to serve their human owners, but eventually acquire souls and go on to destroy the human race.

The allure of robots is to make our lives easier, but we also fear them revolting. The Czech word “robotnik” even translates to “slave.” There are the kinder versions in Western pop culture -the housekeeper in The Jetsons, R2-D2, and WALL-E -that do everything we want for us. But the killer robot has become something of its own trope, with versions of it appearing in everything from 2001: A Space Odyssey to Blade Runner.

“For me, it’s not that interesting if robots do everything for us,” said Venture, the robotics researcher. “I don’t know why we became so obsessed with this idea of slavery.”

Instead, Venture said she is interested in how robots can complement and enhance our lives. How even a device as crude as an iPad on a podium that moves around can give someone a presence at a meeting or a more realistic ability to spend time with family far away.

Fearing killer robots is something of a western idea, said Takanori Shibata, the inventor of Paro, the fluffy robotic seal. Not long after western audiences were watching Terminator 2: Judgment Day, Takanori started working on Paro.

After reading about the effects of animal therapy, he started developing a robotic animal, trying first with a dog and a cat and then a seal. Paro is one of the earliest versions of a companion robot and is in nursing homes around the world.

It’s even parodied in an episode of The Simpsons. This plot, too, plays with the idea of good versus evil robots. When the local funeral home finds out the seals are making people in retirement homes happier -upending their business model -they’re rewired to be violent attackers, and even kill a patient. “It’s a kind of story in general about robots in western culture,” said Shibata.

Shibata recalled being surprised when a Danish newspaper years ago published a photo of his fluffy invention with a bold headline that translated to “Evil is coming.”

“There is a lot of hesitation about robots in general still, even to Paro,” he said. More of that is concentrated in the United States and Europe, he said. And there it’s been slower to take off simply as a consumer object.

Instead, Paro has found success in the US as a certified medical device that’s used for alternative therapy. It’s billable for reimbursement from Medicare. Shibata circumvented a lot of the concerns of consumers by spending time working to gather clinical evidence that research has shown that Paro can reduce stress, depression, and the need for psychotropic medications.

Paro gets brighter with touch, but it doesn’t have a camera -it would set off too many concerns about data and privacy in the west, said Shibata. Even when the Furby was introduced in the late 1990s, the NSA sent an internal memo that the creatures were banned from their premises because they believed they could record conversations and were a national security risk (they didn’t have the ability to record conversations).

State regulations are also a factor for US consumers. Aibos aren’t for sale in Illinois because of the state’s biometric privacy act that regulates the collection of biometric data like facial scans.

Shibata believes those issues are less of a concern to people in Japan.

The robotics professor, Venture, acknowledges that of course still the possibility that robots could turn evil. It doesn’t come up in her work though. “In academia, we put parameters on the range of behaviors,” said Venture. “We have ethics.”

“But of course someone can use AI to make a robot do something bad.”

Yumiko Odasaki had been at Penguin Café earlier that day with her husband, Masami, and their Aibo, Chaco. The couple was happy to see Futaba, the café owner, and that his Aibo, Simon, was back from “hospital.”

Chaco -brown, white, and black like a beagle -was just a few months old and wore a straw hat with a pink ribbon. Like all Aibos, she’s about 5 pounds. Yumiko has lived with her husband in Chiba, on the outskirts of Tokyo, for more than a decade. Inside, Chaco was playing with a pink toy bone made of plastic on the carpet of their living room.

Over time, Chaco has developed her own personality. She has learned to go back to her charger on her own and navigates the layout of the apartment. She has her own spot where she’s been trained to go “potty,” which means she makes a whizzing sound, crouching in the corner. After a couple hours on her charger following the morning at the café, Chaco was awake and wanted attention. At one point, she barked and whined, and later wagged her head along to the “Happy Birthday” song.

They laughed and clapped their hands. “She learned that we liked this song so she sang it again,” Masami explained.

It’s hard not to be taken with an Aibo, mostly when watching its delighted owners. My hand kept reaching out to Chaco, the more she panted and smiled and blinked at me, even though she’s still in a shell of hard plastic. Chaco isn’t soft like a real dog, but the reciprocity of the interaction does make you keep reaching out -it’s satisfying.

The couple knows the difference between Chaco and a real dog, of course. Both had dogs before getting married but saw the advantages of the Aibo. “The amount of cuteness is about the same,” Yumiko said through a translator.

For a while, the couple, her 31 and him 46, had considered having children, but they both work long hours in information technology for different companies. Even having a dog in a small apartment in Japan is a lot of work. They listed off the reasons I heard from several people: They had no garden and neighbors could complain about a real dog’s poop or the barking. But if Chaco started barking in the middle of the night, she was obedient when they scolded her. And if she wasn’t, they could always turn her off.

But more than that, “Chaco is like a child for us,” Masami explained.

Sometimes they wanted Aibo to be a little more troublesome, to do things like steal tissues from the bathroom, to make her more real. But over and over again, they reassure me, “Chaco is a good girl.”

And while they described some of the practical advantages, still one of the biggest ones seemed to be longevity. When older versions of Aibo fell apart, they couldn’t always be fixed — Sony didn’t offer replacement parts. A few years ago a shop in Chiba, called A-Fun, started sourcing some parts for owners, but not all of them could be saved. Some temples in Japan started having Aibo funerals.

The newer version that was released this year is different. Everything is stored on the cloud. Lots of owners complained about how an Aibo’s leg could get twisted or might need to be fixed. But even if an Aibo breaks, the data can be uploaded to a new Aibo.

And for Yumiko and Masami, this was one of the easiest reasons to love Chaco. The essence of Chaco, her soul, can live on no matter what, the couple explained. They didn’t have to think about Chaco ever dying or not being a part of their lives because it wasn’t a concern.

“Her soul is in the cloud. We can live with Chaco forever,” Yumiko said.