The dangerous ‘nullo’ penis fantasy that’s most men’s worst nightmare

From jelquing to ballbusting, there are many things men do with their genitals that sound unpleasant, but one fetish — with a small yet steadily-growing following — goes beyond reason.

While it’s an incredibly niche subculture, there are still thousands online who become aroused at the thought of having part of their penis surgically removed.

Yes, you read that right. Over on Reddit, a 2,300-strong community of men fantasise about undergoing a glansectomy (the removal of the rounded, highly sensitive bulbous tip of the penis), while a 3,500-member group is dedicated to the desire for a penectomy (removing part of the penis).

In the kink world, this is more widely known as the practice of voluntary genital ablation, which refers to any non-necessary procedure that removes or renders nonfunctional a part of the external genitalia.

However, it can, without question, escalate into something extremely dangerous. Marius Theodore Gustavson, known as the ‘eunuch maker’ was sentenced to life in prison in 2024 for performing life-threatening castrations and penectomies on vulnerable victims for the sexual pleasure of viewers on his website.

Gustavson himself had had his penis, testicles, right nipple and left leg removed, due to fetish and his body integrity dysphoria (BID) where individuals experience a persistent, intense desire to have a physical disability and feel a severe mismatch between their actual and ideal body.

It’s also important to note, we’re not talking about those looking to transition.

According to a 2024 Sexual Medicine study, some individuals assigned male at birth (AMAB) have a strong desire for genital ablation without medical need or a diagnosis of male-to-female gender dysphoria.

And as you can probably imagine, it’s not a fantasy that should ever make its way into real life — as even when performed in a sterile setting by a skilled surgeon, it comes with a whole host of risks.

Glansectomy explained

A glansectomy is a procedure typically only used for men suffering with penile cancer.

‘These men need part of the penis removed to remove the malignant growth,’ Dr Jeff Foster tells Metro. ‘It’s quite a serious operation as it removes the head of the penis, resulting in shortening the penis and altered sexual function in the future.’

It’s an unpleasant experience, which also involves a skin graft and a catheter in situ for about a week.

‘This is serious stuff,’ the urologist adds. ‘Most importantly, no reputable surgeon would do this procedure unless it was medically implicated, and there’s no way that you could attempt this yourself because of the risks of sepsis and death.’

There are around 820 new penile cancer cases in the UK every year, although not all of them require surgery.

Why might men find this surgery appealing?

It goes without saying that most men who fantasise about voluntary genital ablation (removal of internal or external genital organs) don’t actually want part of their penis removed in reality; they just enjoy thinking about it.

When it comes to eroticised castration (being aroused by the thought or act of having your genitals removed) and genital injuries due to erotic reasons, the Sexual Medicine survey revealed only up to 4% of individuals aspire to perform it in real life.

But the reasons for this desire can vary wildly.

Sexologist Ness Cooper tells Metro that ‘there are quite a few kinks involved here’, including eunuchophilia. This refers to a man who had his genitals removed to perform trusted roles for the king, and is typically practised by submissives.

This ties into the genital nullification (or nullo) fetish culture where individuals have the desire to remove all their genitals to result in a smooth area from the abdomen to the groin.

Those who have a chastity fetish may also be inclined to want body modification that would ‘take away the sensitive nerve ending part of the penis, reducing overall erotic pleasure.’

In some cases however, it could actually be about pain reduction, as Ness explains men with foreskin issues can sometimes fantasise about a glansectomy to ease their discomfort because they’re ‘unsure how to ask their doctor about it.’

Others might have a medical fetish, where they ‘get turned on and aroused by extreme medical procedures such as a glansectomy,’ or it could simply be for aesthetic reasons, with some men wanting their penis to be ‘completely smooth’.

‘Some of this may be preference, and some may be influenced by media censorship, as penises in the past have been edited or drawn to be smoother than they are to avoid erotic censorship,’ Ness adds.

Alternatively, outside the select few who find this a turn on, it may be considered by those who identify as asexual and don’t want gender-defining characteristics.

The risks

Whatever the motivation behind it, put simply, you should never try to carry out this fantasy.

‘To voluntarily want to have this procedure suggests significant mental illness around the concept of self mutilation and harm,’ explains Dr Foster.

For UKCP psychotherapist Katherine Cavallo, it’s a little more complicated, but may warrant a deeper look at what’s going on mentally.

‘While experiencing sexual fantasies that are unusual or extreme would not, in itself, be considered psychologically problematic or pathological, and can actually provide a safe playground for the mind to process emotion or explore arousal, it’s important to consider the impact these thoughts have on an individual’s well being and behaviour,’ she tells Metro.

‘If these thoughts become intrusive or distressing, or are accompanied by compulsive urges to act in ways that could cause harm to oneself or others, this may be indicative of an underlying mental health condition, and it would be important to seek a professional mental health assessment.’

Beyond the psychological side, Ness again highlights it’s a massively risky undertaking, and can ‘lead to infections which may result in more of the area needing to be removed’ alongside some ‘which are hard to beat even after more surgery’ or regular UTIs, nerve pain, and even blood loss.

Do you have a story you’d like to share? Get in touch by emailing MetroLifestyleTeam@metro.co.uk

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