A new bizarre trend has popped up regarding male genitals in Japan in which men are putting their penises in places they shouldn't.

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Men in Japan are trying to calculate the size of their penis by inserting it in the cardboard tube around which toilet paper is wrapped.

According to Google Search, this technique is not a new one. Men have been doing it for quite some time.

But it suddenly became popular because a Twitter user who goes by the name @urasahou tweeted a diagram to guide men how to measure their penis.

 Twitter/ @urasahou

In this technique, there is no requirement of a measuring tape or ruler. The guide states that one needs to insert his penis into the tube and find its size depending on how much of the genitalia emerges from the other end of the cardboard roll.

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According to the guide, if the head of the penis is not seen bulging from the other end of the roll, then the penis is small. If the penis protrudes up to 2 cm or more, then the size is average.

If more of the head protrudes, then it is huge, whereas it is irregularly large if the entire head protrudes, a report by Metro revealed.

If there is enough space left in the tube after the penis is inserted, it means that its girth is small. If there is not enough room left in the roll, then the penis size is average, and if one is unable to insert their genitalia into the roll without tearing it, then the manhood is giant.

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As per the assumptions made by the Metro, the penis should be erect while men are taking this test.

A standard consumer-size Japanese toilet roll was kept in mind for this guide. These rolls are longer than the size of toilet papers people use in the UK, and hence this assessment is not universal.

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Toilet paper differs from brand to brand, hence such tests are not considered to be too precise. If you really want to know your exact penis size, you can simply measure it and compare it with the average penis sizes.

Another bizarre trend that gained popularity among men recently is "penis whitening". This trend is popular among men belonging between the ages of 20 and 55 years.

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Men get this done in Thailand's Lelux Hospital in Bangkok despite being told about the side effects the laser used in the procedure would have on their penises. This treatment came into existence when a man was unhappy with the dark parts of his groin and he was extremely happy and satisfied after he underwent the procedure.

This strange trend gained popularity when the story about this man was aired on Thai TV.