When Shoji Morimoto was fired from his office job in 2018, his superior had criticized him for lacking initiative and "not doing anything" of value for the company. Joke's on him, because Morimoto, now 41, has since spun a lucrative career out of doing nothing.

Known as the rental "do nothing" guy in Japan, Morimoto's day job involves loaning himself out to strangers who seek someone's company for almost anything at all. These requests can range from waiting for a marathon runner at the finishing line, to being video-called while a bored client redecorates and cleans her room. Once, a client who could not attend a concert with a friend rented Morimoto to take her place.

From the ludicrous to the mundane, Morimoto will simply show up and "do nothing" other than what he was asked to do — except sex.

"I have been put in objectively difficult situations, such as standing in line under the blazing sun, standing for hours in the freezing cold, attending parties with only strangers, and standing alone on a stage in front of a large audience without doing anything," the father of a seven-year-old told CNBC Make It.

"However, no matter what misfortune I have experienced, I feel that it is something special that only happened because I do this job, so I can still cherish it," he said.

Not a therapist

Morimoto's longest one-off task was a 17-hour trip sitting on the same rail line, end to end, from early morning until the last train. "We made 13 laps on the Yamanote (train station) Line," he said.

There have also been several requests for Morimoto to be a listening ear on clients' bad days. However, when it comes to conversations, Morimoto offers the bare minimum and the simplest of answers. In other words, he nods and listens attentively, but makes it a point not to play therapist. 

Morimoto told CNBC he receives about 1,000 requests per year, and lets his clients decide how much to pay him. He used to charge a flat rate of between 10,000 yen and 30,000 yen ($65 to $195) for a two- to three-hour session, and earned around $80,000 last year.

Morimoto introduced the pay-as-you-wish model late last year.

"I charge a voluntary fee, so I don't know if it will be sustainable, but I'm having fun trying to see if it's sustainable," said Morimoto, who added that his goal was not to make a living or sustain himself but to "simply live life and enjoy it."

To put his services to the test, CNBC Make It accompanied Morimoto for two hours, taking him to a piglet cafe in Tokyo where customers can sip on a drink and interact with litters of piglets. 

I'd initially planned to go by myself, but entering a packed cafe and seeing customers in pairs and small groups made me feel a tinge of relief I had Morimoto's company.

There was another perk: He could take photos of me while I played with the pigs.

After a few initial exchanges in my broken Japanese and translation assistance from Google, no further small talk was needed as I left him to his own devices and concentrated on my pig. I then realized the appeal of Morimoto: Clients like me get to enjoy an activity in a social setting without being judged for going solo. Even better, I don't feel obligated to sustain a conversation with anyone when I'm really just there for the pigs. 

While there are no official stats tracking the rental person industry in Japan, the country is home to a slew of rental services for temporary girlfriends, boyfriends, friends and even family.

"This is a good match with the recent needs of Japanese people, who do not seek love or marriage, and do not want the hassle of such relationships, but want someone they can casually go on dates with or have dinner with," Ai Sakata, consultant at Nomura Research Institute told CNBC.

Not just about loneliness

Loneliness may be a reason that some pay for such services, but it's not the only one, said Morimoto and experts CNBC spoke to.

Certain individuals may desire companionship, but others may just be a bit "socially awkward," said Hiroshi Ono, professor of human resources at Hitotsubashi University.

Most Japanese people do not necessarily deal well with confrontation, or even direct communication, the professor added. "People are maybe just too awkward to say, will you be my friend? And so to avoid that awkwardness, they're just willing to pay for it."

Morimoto said a woman once paid him to sit in a corner of a cafe, within her line of sight, while she served divorce papers to her husband — without drawing his attention. The paper signing went smoothly, and Morimoto said the divorcee got an extra dose of courage from having someone she knew nearby.

His presence serves as a security blanket of sorts, temporarily socializing those who are uncomfortable in certain settings, the 41-year-old observed.

"There are many different [favorite] moments in this job, such as when I receive an offer message, when I meet a client, when I accompany a client to an unknown place, when I just listen to a story, and I feel happy in every moment," Morimoto said.

"There was nothing else I truly wanted to do," he said.

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