The pen you’re about to see is one of those shocking products that makes people say they’ve seen it all. This Japanese souvenir actually comes with a live nematode parasite swimming inside it…

Anisakis is a genus of parasitic nematodes that infect various species of fish and can cause anisakiasis  – a parasitic infection of the gastrointestinal tract – in humans who consume raw or undercooked seafood containing larvae of the aforementioned nematode. Some people can also suffer an acute allergic reaction like anaphylaxis after eating fish infected with anisakis. In short, this aquatic parasite is not the kind of thing you’d want anywhere near you, so why would anyone create a pen with a live anisakis worm encased inside?

Photo: Twitter/Tada2547

It’s still early April, so you’d be forgiven for thinking that the pen in question is nothing but an April fool. I know I did, but if the ample evidence on Japanese social media is anything to go by, the live nematode pen is a real thing that you can buy and gift to a special someone to let them know how much they mean to you.

Or you can just keep it for yourself and procrastinate by watching the parasite slithering inside its little tank. I honestly can’t think of a more fun way to spend my workday…

There’s not a lot of information on this bizarre pen online right now, but according to some Twitter users, it was thought up by entrepreneurs in Japan’s Kochi Prefecture, which apart from its agricultural development is also known for its fishing tradition. Apparently, the nematode swimming inside a small, transparent tank embedded in a fountain pen was considered a great selling point. For what, I couldn’t tell you.

So here’s what else we know about this truly bizarre souvenir. According to those who actually bought it, the nematode-containing pen sells for 950 yen ($8.70), which is about 1,000 yen more than I’d be willing pay for it.

The parasite inside is apparently quite active for several days (4 – 5 days by most accounts), after which it becomes more inactive and eventually dies. Then you left with a dead parasitic worm to stare at, which somehow sounds even worse.

Considering the nature of the contents, I’m not sure the nematode ballpoint pen can be purchased online, but I’m sure the people who are in the market for something like this will find a ways to get their hand on it.

Interestingly, Japan is one of the areas of the world where anisakiasis cases are most frequently, due to the consumption of raw seafood (sashimi). The most common symptom is acute abdominal pain, but Wikipedia does a great job of explaining exactly what goes on in your stomach that causes that pain.

“Within a few hours of ingestion, the parasitic worm tries to burrow though the intestinal wall, but since it cannot penetrate it, it gets stuck and dies. The presence of the parasite triggers an immune response; immune cells surround the worms, forming a ball-like structure that can block the digestive system, causing severe abdominal pain, malnutrition, and vomiting,” the Wikipedia article states.

“Occasionally, the larvae are regurgitated. If the larvae pass into the bowel or large intestine, a severe eosinophilic granulomatous response may also occur one to two weeks following infection, causing symptoms mimicking Crohn’s disease.”

Somehow this pen seems even more gross now, doesn’t it?