The Playroom Safety Briefing

[80’s smooth jazz playing]

Before we get started, we’d like to talk for a moment about safety. While you may be a frequent fucker, each playroom is different, and we appreciate your undivided attention while we go through the safety features of our moist, basement death trap. We kindly ask you to remove your gasmasks and cocksucker hoods for the duration of the briefing.

Your poppers bottle is opened, closed, and adjusted like this. Whenever the illuminated sign is on, or people are already nauseous, you must remain seated with your poppers bottle closed.

Portable electronic devices with a urine-proof covering may be used throughout the play. Larger items, such as fuck machines and SodaStreamers® must be securely stowed away.

There are fourteen slings in this playroom. Four in the front, four in the rear, four above you, and two below. Take a moment now to locate your nearest sling, bearing in mind you may already be in one. In case visibility is reduced, a trail of slime will guide you to your nearest sling. Please take off high-heeled shoes before mounting a sling, as they may tear it.

To find an actual exit, look for an illuminated sign barely visible through the thick black trash bag.

In the unlikely event of an actual top appearing, you may be asked to adopt the subby bitch position. It is important to bend as low and forward as possible. If you are seated in the Overdose Bench section, you must adopt this Unconscious Statutory Rape position instead.

In case of sudden excrement event, industrial grade kitchen roll will appear on a holder near you. Pulling on the roll firmly will release its contents on the floor.  

Your condoms are spread on the floor under your sling. Put on your own condom first, and only then assist others. Please note that the condom may not fill. 

This is a non-smoking playroom, and federal law prohibits tampering with, disabling, or insulting people who smoke anyways. You are also obligated to obey any posted placards, illuminated signs, and taunts from the big cigar leather daddy crew.

In case you actually manage to cum, move quickly to the nearest usable exit, taking nothing with you. 



The Laboratory Berlin Gummi Queue: A Mathematical Approach

Hosted every month, but seeing its busiest months during Folsom Europe and Easter, the Gummi rubber party at Laboratory Berlin is the place to go for most rubber heads. On busy nights, it’s however known for its insane queue. Everyone seems to have a favorite idea of how to arrive: some suggest early, some suggest late, and nobody seems to agree. On busy nights Gummi hosts easily over a thousand people. This is easy to notice, since everyone is numbered on the wrist, starting with 1, and by the end of the evening, you see people with numbers over one thousand. Adding to the stress of going to Gummi, the doors are only open for two hours (from 22:00 to midnight), and entry is not guaranteed if the queue is not cleared by midnight. In order to examine this problem from a simple mathematical point of view, let’s make some basic assumptions for the sake of simplicity. These might not reflect real life conditions, but they are necessary in order to generate some graphs. To make it more interesting, let’s also assume that by midnight there are 200 people left out, so the total number of rubberists on a given night is 1200.

Assumption #1: Rubberists’ arrival times to the queue at Gummi follow a normal distribution

Also known as the Gaussian distribution, the normal distribution is a useful simplification for phenomena, although its applications to life sciences are limited, where the log-normal distribution is used more often. In the context of Gummi, the assumption means that the mass of people’s arrival times is centered around an average (which can be changed for scenario planning purposes) and how far out people’s arrival times are spread out is reflected in the standard deviation. Using example values of an average of 9:20pm and a standard deviation of 50 minutes, and sectioned into 10-minute chunks, the arrival of 1200 people would look like this:

Assumption #2: Gummi processes rubberists at fixed speed

In order to calculate the length of the queue at any point in time, we need to know how people are let in. As there is generally a fixed number of people handling arrivals, it’s fair to simplify Gummi to a First-In-First-Out (FIFO, not to be confused with fist-in-fist-out) queue with a fixed speed. Assuming Gummi processes a total of 1000 rubberists in 120 minutes while the doors are open, this means a speed of about 8.3 drones per minute. Calculating the queue length is now simple: the queue only increases until 10pm, and after that is affected by both people arriving and people being processed at fixed speed. Note that in our assumption, at midnight when the doors close there are still about 200 people in the queue.

Calculating total wait time

Calculating your individual wait time is now easy. It is:

(minutes before opening when you arrived) + 
(queue length on arrival) / people processed per minute

The graph below shows the wait time for any arrival time, although it doesn’t take into account that if you arrive too late, you won’t actually get in:

With these example values, it’s easily seen that the waiting time between 8pm and 10:40pm does not significantly change, and with these assumed numbers, people arriving after 10:40pm are actually not getting in. The numbers used in the example are fictitious. However, plotting the graphs with different arrival time averages and standard deviations does not significantly change the flatness of the waiting time curve.

So when should I arrive at Gummi?

Based on this simplified analysis, the arrival time generally does not matter that much. Arriving way too early guarantees fast access after doors open, but you end up spending most of your time in a non-moving queue. Arriving after opening will get you to the end of a long queue, which psychologically might be more stressful. Arriving much later than the opening includes the risk of not being let in at all. Perhaps the Kiwi physicist Ernest Rutherford said it best:

“If your experiment needs a statistician, you need a better experiment.”


Vignettes of Fetish Life

Darkroom culture

Have you ever noticed that darkrooms follow the same cultural rules as rest of the society?

In British darkrooms, it’s customary to apologize if you accidentally touch someone. “Oh, excuse me.” For any play to happen, there has to be the obligatory civilized small talk. “I like that harness. Where did you get it from? I heard Regulation makes great stuff. Can I touch it?”

In German darkrooms, consent means not punching the guy in the nose when he forces you down and him into yourself.

In US darkrooms… well, there are no US darkrooms. Leviticus 18:22.

Frequent Fuckers

Have you ever noticed going to a big event, like the Darklands in Antwerp, is a lot like going on a flight?

First you have to queue for the check-in. Insane queue. If you have a platinum fucker card, also known as a VIP ticket, you can use business class check-in. Smaller queue, better-dressed people.

But then there’s security! What are these security people looking for, exactly? That little pat-pat-pat. That little magic flashlight looking into your bag. Maybe you have a machine gun under your catsuit? A lot of people getting massacred in playrooms, huh?

Let’s face it, you all are smuggling in drugs. There’s more drugs in the playroom over there than in a small city in Bolivia. And they don’t care. They just like selling you those 10-dollar bottles of water at the bar.

So you get in after security. If you are a Platinum Fucker, you can go to the lounge, the VIP area. Drink your one-euro complimentary prosecco, looking down at the masses. Thinking to yourself, if only those people had tried a bit harder in life…

But it’s time for boarding! You all cram into this noisy cramped playroom, just waiting to get out of there. You’re fucking, but also looking at your watch. Shit, I have a connecting fuck in the piss area! If I miss it, when’s the next connecting fuck? I don’t want to be stuck here for hours.

So you run, and make your connecting fuck. You leave in the middle of the night, grab a taxi to some obscure hotel you ended up staying in, saying that you’ll never do it again, but you know you will.

The next morning, when you wake up, you realize you have to post something on Facebook for your family. So you find the nearest Starbucks.

“Great coffee here in Antwerp!”

What’s in a profile

People don’t really think too much about what they write on their profiles.

“I’ll try anything once.” Great! I’ve been reading some books about amputating and I think I have it all figured out now. Got the tools from eBay last week. It wasn’t even that expensive!

“My results say I’m 69% dominant.” Yeah, that’s not gonna work for me. I need at least 71% dominant, and that’s a dealbreaker.

“Just ask.” You mean I have to find that button to send you a message? And then actually write one? You know how hard that is with one hand?

“Not into anything underaged or illegal.” Yeah, right. Sounds kind of suspicious you should mention that. Did your defense attorney tell you to write that in your profile?

“Looking for real bosSSes and some 88.” Come on man, just say you are a nazi. Your code is making us all feel a bit awkward, and not fair to the young ones born in 1988.




Poppers and Viagra®: The history and science of the dangerous cocktail

Poppers and Viagra®, though often used in BDSM and kink, are a potentially lethal combination due to the way they interact in the same signaling pathway. They should never be used together, not even during the same day. I wrote this science-heavy article in an attempt to explain why they can never be used safely together. Trigger Warning: post contains references to enzymes and proteins.

The power of boners: Viagra is born

To understand the surprising link between Viagra and poppers, we need to take a trip back in history to how Viagra came to be the wonderdrug it is.

In the early 1970s, a group of enzymes called phosphodiesterases (PDEs) had been discovered, and by the late 1980s, science was investigating a newly isolated member of this group, PDE5, which was found to relax blood vessels. As human blood pressure is a function of peripheral resistance, relaxing the vessels would be an efficient way to reduce the pressure. Pfizer had discovered a new drug, then called UK-92480, that showed promising results in early studies. However, its effect was short lived, requiring three doses a day.

In addition to the problem of taking three pills a day, the research team at Pfizer also tested the drug in combination with nitrates, commonly used for chest pain, and discovered alarming drops of blood pressure. This was the first hint that this newly discovered drug would not play well with other blood vessel dilators.

Peculiarly, volunteers also complained of two side effects: muscle aches, and increased erections.

For the reasons above, UK-92480 never turned out to be a good blood pressure medication. The power of boners was irresistible though, and in 1997, Pfizer applied for approval for the drug, named sildenafil, as a boner pill, and started marketing it as Viagra.

The science of boners: why cGMP can make you hard (and make you blind)

The human body is an incredibly complex machine. Its actions are regulated by complex cascades of chemicals. Many drugs disrupt this cascade for your benefit. For example, when you take a pill of ibuprofen after a night of drinking, it inhibits cyclooxygenase, which in turn inhibits prostaglandins, resulting in reduced inflammation and pain.

The target of Viagra is cyclic guanosine monophosphate (cGMP), a chemical that among other things, relaxes blood vessels. Relaxed vessels mean stronger erections. It does this indirectly. cGMP is broken down by the phosphodiesterases, and by focusing on the subtype 5 (PDE5), Viagra is able to focus its effects on the corpus cavernosum (the little blood tank in your penis responsible for erections).

Messing with the PDEs comes with a cost, though. While PDE5 is mostly concentrated in the penis and the lungs (Viagra is also useful for pulmonary hypertension), the other PDE members are all around the body. PDE6, a sister chemical, is responsible for making the eye adapt to light, and Viagra mildly fucks around with this as well, resulting in the common side effect of seeing everything blue. This effect is related to the sometimes permanent eye damage caused by poppers

Poppers take a shortcut

While Viagra is a carefully selective and engineered chemical, with an excellent safety record, poppers are equivalent to moonshine.

Poppers, chemically members of the alkyl nitrite family, don’t really care about the regulation PDEs provide. Instead, they convert into nitric oxide (NO), and directly (well, technically via guanylate cyclase) stimulate the production of cGMP, the same chemical Viagra tries to carefully control in your penis. This reaction is rapid and strong, taking effect in a matter of seconds.

This combination of rapid poppers rush of cGMP, and Viagra inhibiting the breakdown of it, has disastrous consequences. Neither drug alone is particularly dangerous, but together they have pharmacological synergy, which means that they do together more than the sum of their parts: a dangerous relaxation of blood vessels, and a drop in blood pressure.

 Ok, I feel dizzy, but so what?

Blood pressure equals life. Even short disruptions in sufficient pressure cause dizziness and fainting, sometimes resulting in traumatic or even lethal injury. Sustained loss of blood pressure due to relaxation of blood vessels results in shock, and eventually starves the body of oxygen and life.

While a 100mg dose of Viagra will by itself cause no more than drop of 8 millimeters mercury (mmHg) of blood pressure, when combined with nitric oxide donors such as poppers, the effect is much bigger. In a 1999 study, healthy volunteers were given both sildenafil and glyceryl trinitrate (a.k.a nitroglycerin, the boom-boom thing, but also a nitric oxide donor with the same mechanism of action as poppers), and the largest reported drop in blood pressure was 51 mmHg. This is a huge drop, enough to be potentially life threatening.

But wait, there’s more! Blue people.

To make things worse, poppers have another way of starving your body of oxygen.  They convert the oxygen-carrying protein hemoglobin into methemoglobin, a version that is unable to carry oxygen. This condition, methemoglobinemia, literally turns you blue. While this in sufficient amounts (such as in an extreme poppers overdose) is lethal by itself, it further makes it more difficult for tissues to get the oxygen they need.

(Methemoglobin also distorts pulse oximetry readings in a very peculiar way, so if you ever meet a bondage top who has a $20 pulse oximeter from China and wants to keep you safe with it while giving you poppers, run away quickly.)

So how long do I have to wait to use poppers after popping some Viagra?

So far we have only talked about sildenafil (Viagra), but unfortunately other erection aids make timing more complicated. While sildenafil has a half-life of about 4 hours, tadalafil (Cialis) has 17.5 hours. Due to this, it is not safe to use erection aids and poppers during the same day, and in the case of tadalafil, perhaps not even on the next day.

Further reading
  • The history of Viagra:
  • How nitric oxide converts to cGMP:
  • Drinking poppers will cause methemoglobinemia:
  • Cardiovascular risk profile of sildenafil:



Guide: Travelling Internationally With Gear

Travelling with gear is fun! A lot of people overestimate the difficulties when it comes to especially airport security, so here I describe different precautions you should take while bringing interesting stuff with you for international trips.

The security restrictions here obviously apply to aviation, based on rules set by the IATA and ICAO, and adopted individually by countries. However, many places around the world regularly also screen train and bus luggage using similar standards, so it’s a good idea to always pack with this in mind.


Item Restrictions
Regular fetish clothing: rubber, leather, lycra Luggage: No restrictions in checked luggage or hand luggage.

: No restrictions, if you have the courage for it.
Heavy gear: motorcycling suits, hazmat gear, diving suits Luggage: No restrictions in checked luggage or hand luggage.

: May need to be taken off for security screening. Wear something underneath.

Luggage: No restrictions in checked luggage or hand luggage.

No restrictions if not containing insignia or appearance with legal powers (such as police).

Customs Warning: Carrying excessively realistic military uniforms with insignia may attract attention of local officials. Patches like “Pussy Patrol” or “Corporal Klinger” might be better choices.

There are a few countries that completely prohibit possession of camouflage. Canada prohibits public wearing of realistic military uniforms. United Kingdom prohibits wearing UK armed forces uniforms in public, although prosecutions are rare.

Gas masks Luggage: No restrictions in checked luggage or hand luggage.

Worn: The Covid pandemic has normalized wearing gas masks in public.
Chastity belts Luggage: No restrictions in hand or checked luggage.

Worn: Chastity belts should be taken off for security screening, or a secondary screening will follow. It is common courtesy not to delay security screening for others, or subject unwilling staff members to details of chastity play.

Restraints, toys and other

Item Restrictions
Lubricants Checked Luggage: No restrictions.

Hand luggage: Allowed in containers up to 100 ml/3.4 oz, in a clear plastic bag like all liquids.
Handcuffs and leg irons Checked Luggage: No restrictions.

Hand Luggage: TSA explicitly allows handcuffs in hand luggage. Other countries will most likely not allow handcuffs or leg irons in hand luggage.

Customs Warning: Leg irons are considered instruments of torture in international law. Their import and export is subject to licenses. In the EU, Council Regulation (EC) No 1236/2005 forbids the import of leg irons. There is no exception for personal use.
Other restraints Checked Luggage: No restrictions.

Hand Luggage: Restraints which are deemed a risk to aircraft safety are not allowed in hand luggage. TSA allows strait jackets in hand luggage, but use your discretion.
Butt plugs and dildoes Luggage: No restrictions, unless your plug is large enough to be used as a weapon, in which case you might want to ease a bit on the ass play.
Electro boxes Note about battery sizes: the largest electro box on the market, the Erostek ET-312, has a battery of 14.4 watt hours. The IATA aviation limit for 100 watt hours is obviously not relevant to most boxes, unless you are doing something absolutely crazy.

Checked Luggage: Electro boxes with built-in batteries of any kind (sealed acid, nickel, lithium ion) below 100 watt hours are allowed, but not recommended. Especially lithium ion powered devices should not be placed in checked luggage. If packed, must be protected against accidental power-on. Electro boxes without batteries are allowed without limitations.

In hand luggage: Allowed with batteries up to 100 watt hours. They should be taken out of bag for separate screening like all electronics. Should be charged to display functionality to security personnel if requested. May be trace swabbed for explosives. If asked about the nature of the device, describe it as a “signal generator”.
Poppers Luggage: Forbidden in both checked and hand luggage for flammability. Commercial x-ray devices, via multi-energy material discrimination, are able to detect abnormal liquids and may cause further scrutiny.
Shock collars Luggage: No restrictions in hand or checked luggage.

Worn: should be taken off for security screening.

Customs Warning: Shock collars are illegal to import in some countries. There is generally no exception for human use only.
Medicine Viagra and other erection aids are usually prescription medicines. Standard rules for posession and importation of personal medicine apply.
Military equipment Military equipment and parts of them are subject to international controls. In the US, International Traffic in Arms Regulations (ITAR) regulates the movement of such goods. There is no exception for personal use. The list of items controlled is surprisingly large, and found in the United States Munitions List.
Whips, crops, batons, stun guns, other weapons Checked luggage: No restrictions.

Hand luggage: Weapons or objects potentially usable as weapons are not allowed.

Customs Warning: Public possession of offensive weapons is illegal in many countries around the world.