What is having sex in the wrong hole? What this generally means is that when penetrating, the man inserts himself into the anus instead of the vagina, usually on accident. While anal sex can be pleasurable for both partners if the woman is properly prepared, accidental insertion in the wrong hole can be a surprise that's not only unpleasant, but particularly painful. Even when an accident, it can definitely kill the mood.
So how can you prevent having sex in the wrong hole? The guy can be careful to insert himself into the vagina. An even more reliable, and sometimes very arousing, alternative is for the woman to take hold of the man and insert him herself. Going this route means that there is no chance of the penis going into the anus, and having sex in the wrong hole is prevented. It also lets the woman take control of the penetration, which can be very exciting for both partners.
Just because anal sex is sometimes referred to as "having sex in the wrong hole," that does not mean that many couples do not partake in the activity, with many couples enjoying it immensely. It just takes a different level of preparation than typical vaginal intercourse. The man should definitely be wearing a condom, preferably a lubricated one, and the woman's anus should also be properly lubricated. When everyone is prepared, anal sex is anything but "having sex in the wrong hole." But when it is an accident and a surprise, it not only feels wrong, it hurts. And that is definitely a problem.