Most gay men (around three-quarters) engage in fucking as either the top or bottom. The majority (70%) of gay men in Australia are versatile, 18% are tops only, and 12% are bottoms only. For the bottom, pleasure comes from stimulation of the sensitive nerve endings of the anus when you are being fucked.

The anus is just beyond the sphincter (the circle of muscle that is the entrance to the anus). The area beyond the anus is the rectum, which has few nerve endings. Pleasure also comes from having your prostate stimulated.

The prostate is a walnut-sized gland found in men only. It is located alongside the rectum, where the base of your cock ends inside you, directly below your bladder. It is sensitive when touched from inside your arse (by a cock, or a finger or toy): this can make orgasm more intense.

If you are HIV negative, being fucked without a condom puts you at very high risk of HIV infection. Unlike the lining of your throat and mouth (or a vagina), the lining of your anus and rectum isn’t tough. It can easily tear during fucking (or when a sex toy or finger is inserted). Bacteria and viruses can enter the body though these tears.

This is why anal sex without a condom is an easy way for HIV and other sexually transmissible infections to pass from one person to another. Also, unlike your mouth (or a vagina), your arse doesn’t lubricate itself. Using lots of water-based lube during fucking will reduce the likelihood of tearing or abrasions of your arse. Douching increases the risk of HIV infection because it removes the mucous lining of your arse. Also, using a douche with a nozzle can cause tiny cuts.

If you are HIV positive, then pulling your cock out before cumming inside someone’s arse is not enough to protect your partner from infection. He can still get infected from HIV in your pre-cum, which can enter his bloodstream through damage or cuts in the lining of his arse.

If you are HIV negative you can’t pass on HIV even if you cum inside someone’s arse. However, if the guy you are fucking is HIV positive, you can get the virus through the meatus (the opening of your cock), through the cells on the inside surface of your foreskin, if you are uncircumcised, or through any tiny cuts or abrasions. Although being fucked is more risky if you are HIV negative, being the top does not mean you are protected from HIV.

Viral load tests measure how much HIV is circulating in the blood. HIV treatments can reduce the amount of virus to levels that are too low for current tests to measure. This is called ‘undetectable viral load’. This doesn’t mean the virus has disappeared entirely. Recent studies show that HIV is much less likely to be passed on when viral load is too low to be detected. Many scientists now estimate HIV treatment to be as effective as condom use in preventing transmission between couples where one partner is HIV positive. However, these studies of viral load and HIV transmission have focused on couples in regular relationships, so it is not known to what extent these findings apply to transmission between casual partners.

The aim of treatment is to suppress viral load. In many people, viral load will become undetectable. Others may find they still have very low levels of detectable virus (i.e. <400 viral copies per ml. of blood) but this level of virus is unlikely to have a significant impact on their health or on the chance of transmission to their partners. There is a greater likelihood that an HIV-positive person can pass on HIV during the first six months of treatment. Also, STIs (sexually transmissible infections) will increase the risk of transmission. To minimise this risk, regular testing for STIs is required; as is consistent adherence to HIV treatments to achieve and maintain an undetectable viral load.

Many HIV-negative men think that someone who is HIV positive will tell them before having sex or will always use condoms. However, expecting people to disclose HIV status is not always realistic, especially at beats, or in sex-on-premises venues, where people rarely get to know each other—or even talk—before having sex. Many HIV-positive men think that anyone who is willing to fuck without condoms must also be positive. This belief is not true either. A sex partner who does not suggest using condoms could be: HIV negative and assuming that you are too; or HIV positive and assuming that you are too. When there is no discussion, you cannot know what he’s thinking.

You cannot tell by looking whether someone is HIV positive or not. Most people with HIV look the same as they did when they were HIV negative. Someone who is young, healthy or attractive may still have HIV.

Talking about HIV is better than making assumptions. However, there are still risks. If you are HIV negative, looking for casual partners who are also HIV negative so you can fuck without condoms is not a very reliable way of avoiding HIV infection. This is because he might be HIV positive and not know it. (When was he last tested? Has he had sex without a condom since then? With how many partners?) If he has recently been infected his viral load is likely to be very high. This means that fucking without condoms will carry a high risk of HIV being passed on.

Oral sex (sucking) is a very common sexual practice. It is extremely pleasurable for the guy getting sucked off. If you are not used to sucking it’s important to prevent your teeth getting caught on his cock. You can do this by slightly curling your lips around your teeth. Another problem is gagging, which can happen when his cock hits the back of your throat. This can be managed in a few ways: by timing your breathing around his thrusting (i.e. breathe in when he pulls his cock back); by gripping your hand around the shaft of his cock to control the thrusting; and tilting your head back to make a straighter line from your mouth to the back of your throat.

The risk of getting HIV through oral sex is extremely low, even if you get cum in your mouth. However, a few men have become infected with HIV after sucking off an HIV-positive man. This happens because of cuts, sores or ulcers in the mouth, gum disease, recent dental work or another STI.

• Keep your gums healthy: this will reduce the risk of HIV transmission during oral sex.
• Get regular sexual health tests. An infection in your throat increases the risk of HIV transmission.
• Avoid brushing or flossing your teeth within an hour or so of oral sex—brushing and flossing can cause tiny cuts to the gums.