Husband and wife team Rachel and Jun are "J-vloggers": YouTubers who film their lives, decoding for the masses a nation that's seeing big spikes in tourism and global interest.

Every country in the world merits books and articles devoted to unpacking the nuances and quirks of its culture. But on YouTube, interest in one particular country is pervasive: Japan.

This video of a red-headed woman playing with dozens of squealing foxes in Japan’s “fox village” has more than six million views. The “Idiot’s Guide to Japanese Squat Toilets” has three million, and “Modern Japanese Table Manners” has almost two million views.

They’re all created by Nagoya-based husband-and-wife vlogging duo Rachel and Jun Yoshizuki, who run the YouTube channel Rachel and Jun. Their on-the-ground accounts of daily life in Japan have been viewed more than 200 million times.

They belong to a community of “J-vloggers”: YouTubers who attract millions of views by sharing their insights into Japanese culture. Often (but not always) expats, these users upload anything from a tour of a Japanese high school, to what it’s like to stay in a tiny room in a capsule hotel and what it’s like to be multiracial in Japan.

The rise in J-vlogging is part of a bigger trend: YouTube is more popular in Japan than ever. “The hours of content uploaded from YouTube channels in Japan has more than doubled between 2016 and 2017,” says Marc Lefkowitz, YouTube’s head of creator and artist development for Asia-Pacific.

For Rachel and Jun, making videos about Japan for their 1.8 million subscribers is a way they make a living. They’ve also launched spin-off channels, like the cooking-centred Jun’s Kitchen, which has two million subscribers.

The pair decline to share how much money they earn from YouTube, and say that it varies widely depending on factors like the amount of views and the ad rates in the various countries their viewers reside in, which is the case for many YouTubers.

They say J-vlogging has opened doors to other work: the couple has been offered voice acting roles in video games and Rachel has been approached to do modelling. That, plus sponsorships and donations from viewers on crowdsourcing site Patreon (two staples for many successful YouTubers), all help bring in cash.

People want to virtually travel here, learn more about the food, customs and culture - YouTube's Marc Lefkowitz

But the couple never set out to become internet famous. When they started their channel in 2012, they were in a long-distance relationship (Jun is Japanese and Rachel is American) and used the platform to share videos.

It didn’t take long for others to get interested. They only had a dozen or so subscribers when they made “What NOT to do in Japan” early in 2012, which quickly racked up hundreds of thousands of views.

But the road to vlogging success is not an easy one.

“There was a period of maybe two or three years where we had no days off – it was seven days a week. Every waking hour was devoted to video-making, editing videos, thinking of ideas, filming, social media, going to meet-ups. We ended up so sick,” Rachel says. “I was getting sick every couple of weeks and pulling all-nighters several times a week to make my arbitrary deadlines that I set for myself.”

Burnout among YouTubers is not uncommon. But the thing that kept Rachel and Jun going was making videos they genuinely cared about – and the Japan-hungry internet responded.

“All of us [J-vloggers] get comments from our audience that they went to Japan because of us, or they started studying Japanese because of our videos, or they visited this city because we made a video about it,” Rachel says.

Does that make them grassroots cultural ambassadors? “I personally don’t consider myself an ambassador,” Jun says, and Rachel agrees. “We started YouTube just because we wanted to.”

[J-vloggers] get comments from our audience that they went to Japan because of us, or they started studying Japanese because of our videos - Rachel Yoshizuki

They say one of their most recent videos, “50 Facts About Japan”, took over 250 hours to make, longer than any of their past videos. The 11-minute long list covers road construction barriers shaped like cute animals, how Japanese people still buy CDs, how birth control pills are widely unpopular – all things the couple have thought about for years but that might be little-known among their audience, which represents 190 countries and territories. It’s about 30% in the US, and the rest is everywhere from Japan itself (where many Japanese speakers watch to learn English, the pair say) to Taiwan, Germany, Brazil, Spain and Sweden.

So, why do so many people love watching J-vloggers?

Global interest and international visitors could have something to do with it. Tourism numbers are rising at lightning speed – 250% between 2012 and 2017. The World Tourism Organization says that Japanese tourism has seen six straight years of double-digit growth, with a record 28 million foreign visitors travelling to Japan within the last year, a figure especially powered by China. The government aims to attract 40 million visitors in 2020 for the Tokyo Olympics.

“This is particularly interesting to me as it correlates with the rise of J-vlogging,” YouTube’s Lefkowitz says.

He adds that popularity of Japan’s pop culture and interest in its cuisine and history play a big part in both tourism and J-vlogging's rise to prominence.

“People want to virtually travel here, learn more about the food, customs and culture,” he says. “It has also translated into incredible growth on our platform.”

But foreign visitors expecting to stroll through Tokyo and spot androids or Pokémon cosplayers at every turn are going to be disappointed.

While misconceptions about every country exist, Japan in particular seems to get a specific portrait painted of itself in international media, which likes to focus on the country’s weirder elements. Example: game shows in which contestants blow a live cockroach through a plastic tube into each other’s mouths.

“I think it’s really nice for [viewers] to get a down-to-earth, genuine perspective from actual people,” Rachel says – many people think Japan is “a crazy place, and then they get here and it’s just another country.”

In fact, their channel sometimes touches on the more negative aspects of life in Japan. When Tokyo Medical University admitted earlier this year that it rigged test scores to admit fewer women, Rachel and Jun made a video chronicling dozens of Japanese women’s reactions on social media, shining a spotlight on sexism in a country that’s been slow to fully embrace the #MeToo movement.

But much of the channel is about cultural differences. During my Skype interview with them, I got to see in real time the cross-cultural back-and-forth that’s coloured so many of their videos. At one point, Rachel started speaking about how the world is often fed the image of “wacky Japan” with its slapstick game shows and boisterous comedians.

Jun interrupts: “I thought you guys thought Japanese people were shy?”

Rachel: “Well, there’s that, but…”

And voila: there's the type of the interaction that characterises so many bicultural relationships – asking each other why you do this, why you think that. It sparks the same kind of conversations between partners as it does among the global audience watching J-vloggers' videos.

“It’s really helpful to have both perspectives in a video,” says Rachel. “I think that’s one of the reasons our channel has managed to do relatively well.”

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Bryan Lufkin is BBC Capital’s features writer. Follow him on Twitter @bryan_lufkin.โ€ฏ 

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