1. The average length of heterosexual intercourse is 7-14 minutes, start to finish.

Homosexual women, on the other hand, spend at least 30-45 minutes, and often can take more than an hour. There’s no need to rush anything, but given the amount of porn where sex seems to last forever, more and more men seem to think that what their partners are looking for is just…lots and lots of thrusting, that lasts for a really long time. This isn’t really comfortable for anyone, and can get pretty boring, eventually. Try to read your partner’s cues and see if both of you are still enjoying yourselves; if you are, by all means keep going. If you’re not, finish up and have a snack.

2. When you’re aroused, your nose gets bigger.

Your nose has erectile tissue in it. Repeat: your nose is basically the same as a clitoris or a penis. When you’re aroused, it fills with blood and becomes engorged the same way that genitals do…which can sometimes result in it swelling completely shut, which is bad news for anyone who likes giving oral sex.

3. People smell really good when you’d make nice healthy children.

The Major Histocompatibility Complex is a group of genes that is related to odour…specifically, body odour. When body odour is too similar, that means two people share too many common genes to produce viable offspring — there’s a risk of inbreeding. When body odours indicate that genes are different enough to make good kids, they start to smell REALLY good. The classic “sweaty t-shirt” experiment got a group of men to wear plain white t-shirts for a few days, and women then had to rate the smells of the t-shirts — the researcher, Swiss zoologist Claus Wedekind, found that women were more attracted to the smells of men with whom they were MHC compatible. This is not to say that smell is the only factor in attraction; there’s a lot more to it than that. But if you ever find yourself strangely drawn to someone (in a sexual way) and unable to explain it, chances are, you smell nice and genetically different.

4. A lot of the sex ed you get in school is not as comprehensive as you think it is.

I have met people over and over again who say their sexual education courses in school amounted to nothing more than pamphlets about growing hair in different places and AIDS scare tactics. My own sex ed course was part of “Health” class, so some days we talked about periods, and some days we talked about brushing our teeth. There is a lot that gets left out, sometimes not even for nefarious reasons. It can be difficult to go into any situation thinking you know what it’s going to be like, and actually having no clue…then having to figure it out, get confused, or wonder why nobody in school mentioned that it’s okay to like boys AND girls, or feel like you don’t have a gender.

5. If you’re an anxious person, “do what comes naturally” is not at all how you have sex.

Nothing comes naturally. Even walking on your feet is a learned skill that you pick up from watching everybody else around you, then practicing and falling over a lot and whacking your face on the coffee table. There isn’t really an equivalent slow learning and observation process for sex, and if you have any kind of anxiety at all, even telling someone you like them enough to have sex with them might have been all the confidence you could muster! I actually suggest doing a lot of background research: watch a lot of different kinds of porn (preferably feminist porn), read some books (especially the old Joy of Sex with the really hairy couples), and try not to worry too much about making mistakes.

6. There’s a chance of surprise goo.

Dan Savage recently addressed a question from a man who was amazed and appalled to discover that his partner’s vagina did not effectively retain all fluids he deposited into it, at least until she could safely get to the bathroom and squeegee herself out. Aside from it being pretty ill-informed and misogynist to insist that tight vaginas can hold sperm more effectively, after heterosexual penetrative intercourse, vaginas emit something called “flowback”. This fluid is a mixture of secretions, usually containing sperm (interestingly, if she has an orgasm, the flowback contains LESS sperm), that are almost forcibly ejected from the vaginal canal about 30-45 minutes after intercourse. This is why people with vaginas may clean up and then, when they’re just sitting down to dinner, get an unfortunate surprise in their underwear.

7. Semen turns into rubber cement if you try to wash it off before it dries.

If you have a penis, you have probably experienced this. If you don’t, you might never even have heard of this. Semen contains different kinds of proteins — the two that are relevant to this particular discussion are semenogelin (a coagulating protein) and prostate solution antigen (PSA – a dissolving protein). Semenogelin gets solid and sticky especially around non-alkaline substances — like water, or the acidic environment of vaginal secretions — and then the PSA kicks in to break it down to a more liquidy liquid anywhere from 5-40 minutes later. PSA is very water-soluble, and gets washed away in the shower, removing the semen’s ability to liquify. If you want to make sure you can get semen out of whatever it’s on, wait a few minutes for the PSA to kick in and you should be fine. Some people report that using soapy water right away breaks down the proteins, so that’s a good option too.