Japan is known for it's ingenuity, efficiency, and work ethic - traits that helped the country become a booming economic powerhouse after the end of World War II. However, it all came crashing down in the 1990s. Japan entered a recession (known as the "Lost Decade") that continued through the turn of the century (the "Lost 20 Years") and still lingers to this day. 

How could a seemingly unstoppable force with decades of momentum come screeching to a halt? Economists say the bubble burst. With low interest rates, Japanese banks were lending more money with less regard for vetting borrowers. Inevitably, the economy crashed when borrowers couldn't repay their debts.  

Sounds like an open and shut case. Except. Economists seem to forget another thing Japan is well known for.

Tentacle porn.

Tentacle porn is porn that features tentacles. It was created to skirt the censorship laws that forbid depiction of obscenity. And most importantly, it rose to prominence in the late 1980s[1]. Right before the onset of the economic crash.

Coincidence? 

Maybe. Maybe not. It's unlikely tentacle porn caused the recession per se, but it certainly could have been a warning that things were going downhill. A cry for help almost. After all, things can't be going well if the population is busy masturbating to cartoon tentacles. Maybe the recession wouldn't have happened if Japan had real porn to beat off to.

It's hard to say for sure but one thing is clear. Things have only gotten worse. Less Japanese are getting into relationships, having kids, or even having sex, instead turning to "virtual-reality girlfriends and anime cartoons"[2]. If tentacle porn foretold a crash, this new trend points to a continuing downward spiral for the Japanese economy. The Lost Decade that started in the 1990s may soon enough turn into the Lost Century.

From an investment perspective, the plan is clear. Do not put any money in the Japanese economy. The yen has been decreasing in value and once innovative companies like Sony and Toyota aren't dictating the marketplace anymore. The only thing to look out for is a complete change in social standards. It'll be safe to invest in Japan again when pixelated genitals and hentai are no longer commonplace.  

So tentacle porn and economic crash. This could be a question of what came first, or more recently, who's coming at all. 

Sources:
[1]http://www.wweek.com/bump/2016/12/06/a-brief-history-of-tentacle-porn/
[2]https://www.theguardian.com/world/2013/oct/20/young-people-japan-stopped-having-sex