This is a good topic.
So what I want to talk about is "aversion" and how one person's aversion can creep into cultural thinking.
Let's say that you have an allergy to shellfish. Many people do. Keep in mind that there were hundreds and thousands of years before benadryl so for eons animals and people had to build up immune systems reacting to the presence of bacteria, poisons, and all kinds of other things. There's a point to this, I promise.
Many members of a species died because of these allergies. Many humans today would die if they couldn't get the right medication soon enough. It's crazy to watch how some people's bodies respond to a thing they're allergic to. But I want to hammer the point that this was life and death. And if you didn't know or understand the cause then you would simply demonize whatever fruit or thing you saw that contained the allergen.
What happens overtime is that stories of different SOURCES of allergins get group together and people decide what's dangerous to consume based on that. But something else happens... Evolution. So when enough people died their inability to handle the allergen or virus died with them and the ones who survived were less likely to have children who couldn't handle the same diet. And so they grew immunities. But this doesn't stop the stories and so certain things were simply avoided rather than allowing themselves, as a community, to build up an immunity to those things.
What the hell does this have to do with aversions? Slowly getting there.
Again, when we don't know the real source of something we demonize the vehicle. Are there not sexually transmitted diseases? Yes there are. Could ancient peoples test for these diseases and isolate them? No. Could they give each one a name and study them under a microscope? No, they couldn't. Can you get an STD from having normal sex? Absolutely. But all STDs aren't fatal. Some simply give you a rash or some kind of irritation.
So let's think about this.
If our ancestors... were going down on each other... and we do have reason to believe this from ancient artworks... then they also experienced sexually transmitted diseases. And we know that many "pathogens" are blood-borne. (You can google all this if you want to learn more)
Now if we look at the bible we can see that the Israelites were afraid of women who were on their periods. Why? Because they were afraid of their blood getting on stuff and spreading sickness or disease from the contamination. Hospitals are careful about contamination, especially bacteria, because it can find its way into open wounds or surgical cuts which can cause patients to infect each other without even coming into direct contact.
Now... today... do we force our women to spend their menstruation in separate rooms like they did? No. We have so many new products to disinfect and make sure the blood is controlled. So we can understand their aversion to women on their cycle but we don't have to share or copy that same aversion.
At the same time, people can have STDs. But likewise, we have tests for that. And if we avoid having sex with people who have STDs or STIs then we can avoid spreading them. It still happens but we're getting better at it.
So do you talk to your children about not kissing, not having sexual contact? Or do you talk to your children about the dangers of diseases and how they are transmitted? If you simply say "Don't do this." and your child doesn't understand why... you are being naive if you think you are protecting them. Why? Because if you don't give them a good reason or they come to a better understanding than what you (previous gen) display, they will either do that thing out of their own choice or they may do that thing out of rebellion. Some won't. Some will not do the thing because they simply accept the cultural bias or narrative that its just "bad/evil". But you should teach them how to protect themselves and teaching them about virus, bacteria, and things like that, IMHO, is extremely important.
Do you just tell your children to wash their hands before they eat? Do you just tell your children to cover their mouths when they cough? Or do you explain why? It's the explanation that gives them the real understanding that they can carry on. Otherwise, it just becomes a bandwagon that people run after blindly.
So when it comes to oral sex/stimulation... why is it wrong? Does the bible even say its wrong? According to the bible ALL sex is considered "unclean". This about that. Why? Why is even the sex between married people considered "unclean"? It is simply because of the exchange of bodily fluids. People who had sex were considered unclean "until evening". How do you fix that? Wash yourself. This is easier today than 2000 B.C. in the desert. Trust me.
And this physical cleansing became a ritual that symbolized spiritual cleansing as well (baptism).
So oral sex isn't wrong, but you need to limit your exposure to disease, bacteria, etc. And we all know that women can have bacterial or fungal infections. Consider the "yeast" infection. Women have healthy yeast that normally live in their vagina. There can be an overgrowth of this. Good bacteria live all over our bodies and they fight "bad" bacteria. We also have bacteria that live in our mouths and digestive tract. So what happens when an overgrowth of bacteria in vagina meats bacteria in mouth? A man can get a yeast infection in his mouth. So yes, if your woman has an infection or doesn't do anything to keep her vagina clean, then that raises the likelihood of infection spreading to the man. And sometimes you can smell it because its actually bacteria that release odor.
So if your woman smells like fish... there is an overgrowth of bacteria. You may want to leave it alone.
In general, I like to use mouthwash afterward. Why? It's not the act we should fear. What we need to understand are the RISKS that come along with the act. So instead of just simply having that aversion to the act, think about why that aversion exists. It's not simply because your ancestors thought it was nasty. Are you going to teach your children not to use tongue when they kiss? No, because you're not worried about that. So it's not that our ancestors thought it was nasty. It's that they knew it came with risks and they didn't have products back then to clean and reduce the population of bacteria in the vagina.
Again, today we have antibacterial soap, mouthwash, anti-microbial douche, etc. So teach your children about SAFE sex, don't just scare them with general boogeymen that they will grow out of. Teach them about the dangers so they can limit their exposure and keep themselves clean. Once they know the risks they may choose not to do it at all on their own. Or maybe not. But they'll be safer and they'll understand the reasons behind your concerns. And that's what will protect them.
All children think it's nasty growing up until they get older.