Why do male actors have mystery paper cups during porn shoots in Japan?

As we continue to watch the new season of the Netflix show The Naked Director and its galvanic portrayal of the 1980s and 1990s Japanese adult video industry, porn shoots have been on our mind even more than usual.

In behind-the-scenes photos of porn shoots, we are amazed by so many things.

How many staff are involved and how, if you’ll excuse the pun, hard the work it is, getting the right angles and lighting. In these corona times, as two pictures recently shared by the AV director Daiki Kato (Samoari) demonstrate, they also have to wear masks (except the performers).

How tight, if you’ll excuse another pun, the locations often are, especially when there are more than two performers and the crew.

How difficult it must be for the performers to do their work so well in such conditions — and for many hours.

But many people have noticed something else. A mysterious detail hidden in such behind-the-scenes photos. The male actor often has his finger in or over a paper cup held off to the side by a dedicated member of the crew.

Huh? What could that be for?

This has been a question on social media and forums for a long time.

Is a cup of cold water, dipping his finger in which provides an incongruous physical sensation that distracts the man and stops him from climaxing too soon?

There is a theory that it’s for making realistic sounds during penetration or oral sex. To get the timing right, the actor has to do it. But if so, it would require incredible drummer-like hand-to-cock coordination and be an unnecessary distraction when the actor surely needs to focus on his performance. They could just add something in during the post-production, right? After all, they already have to pixelate the genitals by law, which is a whole subindustry in its own right with technicians dedicated to providing the “mosaic” service. What more trouble would be it to add a sound effect?

Another theory is that it’s fake semen. Since porn actors are actually almost always wearing condoms, those creampie (nakadashi) scenes at the end of the action are fake. To achieve it, the actor quickly pulls out after finishing (inside his condom) and slides his fake-cum-coated finger into the vagina to achieve the dripping look. Only the actor is contractually and ethically allowed to do this. But what about the blowjob scenes when the actor also has his finger posed over the cup? Besides, there are plenty of genuine creampie AVs out there.

So, what’s the answer? It’s apparently the simplest one. And it was confirmed by none other than Shimiken, probably Japan’s most famous male porn actor.

It’s lubricant.

The cup has lube that the actor can quickly dip into before penetrating the female performer. This is a must since shoots are long and the female star, for all her talents, may not always be wet enough and the setting might not call for on-camera use of lube.

In another demonstration of the care and professionalism of Japanese porn, there are even two types of cup: brown paper cups for anal lube and white ones for vaginal lube. The actor may also have anal lube waiting on his shoulder for ease of application.

This still doesn’t quite explain why actors seem to have their fingers in the cups constantly — even while penetration is already ongoing. And why do they need to have lube ready when getting a blowjob?

So perhaps porn shoots still have a few mysteries to reveal yet.