Chapter 4 Scene 2 Potluck

Late at night on the weekend, the man and woman, both in their late 20s, were getting ready for bed.While they were busy with the chores around them, they frequently entered and exited each room.Both are completely naked, but for them nudity is so commonplace that they no longer immediately associate it with "sex."Also, they don't get as excited about seeing each other naked as they used to.To be honest, the two rarely look at each other's bodies these days.Tonight is a weekend night, and both of them know in their hearts that they have to have sex before they go to sleep.However, this form of sexual intercourse has become a routine for each of them.At this moment, they occasionally pass each other in the room, but there is no atmosphere of sexual foreplay.

In fact, the last time they had sex was a week ago, last Saturday. When they first met 4 years ago, the two had sex at least once a day (except when her period was on hold).At that time, if they heard "once a week", they would probably think it was a joke.Now, although their practice is "twice a week", the frequency of "once a week" is getting higher and higher.And since two months ago, they decided not to take any contraceptive measures. They give up contraception, not because they are eager to have children.At least so far, their friends in their thirties have not come to enthusiastically teach them how to "be human".As for having children, they prefer to let things take their course.Moreover, since they stopped using contraception, the possibility of pregnancy brought them a faint excitement. At first, they even had intercourse three or four times a week.However, this week is special.Some nights they spent separately outside, there was an air of inexplicable indifference between the two of them, and both seemed consciously or unconsciously to avoid making love.Until Saturday morning, they drove to visit the woman's sister's house together, and the romantic atmosphere of the past had not been restored.Even at this moment, when they were both in bed and ready for bed, they could still feel the coldness of the week.First, the man tentatively reaches out to touch his spouse's naked body, and following this action, the two immediately begin their routine.

The man first tenderly kisses the woman's face while touching her breasts with his hands.Gradually, the two began to kiss each other harder.The man touched the woman's thighs and knees with his hands.After a while, he bent his head down to suck her tits, while the woman ran her hands lazily over the man's back and buttocks.Tonight, she was having trouble concentrating as usual.Like this moment, the conversation with her sister in the morning came to her mind.However, the moment the man put his hand between her legs, the woman's thoughts immediately returned to reality.At this moment, the man brushed back her long pubic hair with his hands, and put his fingers between the labia to test whether her vagina was wet enough.He thought she was ready, but the woman knew her body wasn't ready, and she didn't want to let him penetrate.So she reached for his cock, holding it lightly over and over again.The woman's movements also seemed to test his readiness for intercourse.However, in fact, this is her plan to delay the attack.The man stopped what he was doing, and then began to rub his fingers against the woman's genitals.Although he didn't touch the woman's pussy, he could feel (or imagine) with his fingertips that the woman's vagina was getting wetter.The man releases his hands, adjusts his body position, and becomes face-to-face with the woman.Still holding his cock in her hands, the woman waited for the right moment to guide the distended cock into her vagina.For a few seconds, the woman put her hand between her vagina and penis, she didn't want the man to move too hard, let alone come too quickly (because she wasn't wet enough herself).However, she soon realized that the situation was out of control, so she had to let it go.The man first jerks back and forth gently, and after a while, the woman's vagina is finally filled with lubricating fluid, and the man's penis is fully inserted into the vagina.

Before the vagina is completely wet, the woman's attention is completely focused on the two genitals, and she concentrates on whether the man can penetrate smoothly.However, when the pussy became completely wet and the man began to jerk back and forth as usual, the woman's mind returned to her sister.Occasionally, the man's movements made her feel uncomfortable, and only then did her consciousness return to reality.But even if she is absent-minded, with her years of experience, the woman can still respond to the man's movements with a low voice from her throat.At this moment, the woman's consciousness suddenly jumped to Wednesday night, and she thought of the man.While with friends that night, the man came up to her and approached her.At this moment, the woman fantasized in her heart that it was that man who was pressing on her.Her heartbeat was getting faster and faster, her breathing was getting faster and faster, and there was a higher voice in her throat.However, just when the illusion was about to take shape and she felt that she was about to reach an orgasm, the man suddenly made a particularly clumsy movement.All the illusions immediately vanished at that moment.The timing missed.The woman quickly senses that the man is ejaculating.She groaned as the man contracted.The penis in the vagina began to gradually shrink, and their bodies began to relax together.The weight of the man on her body suddenly became unbearable, and she coughed softly.The man's shrunken cock had already withdrawn from the vagina, and he came down from her, and the two embraced as usual.At this point, they both feel guilty about not being able to do more for each other.The two fell into a melancholy atmosphere at the same time.But then, before the two are about to fall asleep, they cajole each other that "everything is great".

Usually, the average person has sex with their long-term partner at home.What's more, this pattern of intercourse quickly becomes a routine between the two, yet routine intercourse plays a surprising role in the pursuit of reproductive success for both sexes. In this chapter we will further explain the behavior of sexual intercourse between long-term partners.Since most of the scenes introduced in this book will involve various situations and various characters, in the first few scenes (Scene 2 to Scene 7), we will first take a pair of couples as the protagonists and introduce them respectively. their journey from routine intercourse to pregnancy.Especially for pregnancy, we will give you a detailed introduction about the whole background process of pregnancy.

Before explaining the first scene, let us first take this opportunity to explain a little about the basics of human sexuality.Perhaps readers already know most of the basics, but we believe that there must be some surprising parts in our description.The explanations we have given here may sometimes be a little too tedious.But these explanations can help us understand other parts of the book, some of which are related to other more interesting areas of human sexuality, such as male and female masturbation and female orgasm. No matter who the readers are, as long as they have lived with the opposite sex for several years, they can probably find some very familiar things in this scene.In fact, it is precisely because we are too familiar with these experiences that everyone is likely to overlook some subtle behaviors of the two people in the scene.In fact, the couple in the scene had lived together for four years, and during that time they had had more than 500 sexual intercourses, none of which resulted in a woman becoming pregnant.Of course, they have taken contraceptive measures, but they will occasionally be negligent, and the woman should probably become pregnant because of it.However, the woman never conceived for a long time.Even now, they've stopped taking any contraceptives, and the women are still not pregnant.

In other words, the purpose of the couple's five hundred repeated intercourses was clearly not to conceive.For the average man and woman, no matter whether they live in the wilderness of the Galahari Desert or in a high-end mansion on the outskirts of the city, in the lifetime of all men and women, on average, each person will have sexual intercourse 2000~ 3000 times.Before the invention of modern contraception, most people had fewer than seven children.If calculated by a rough algorithm, it is equivalent to about every 500 sexual intercourses to give birth to a child.Regardless of whether this algorithm is correct or not, the conclusion is clear: from a reproductive point of view, basically, we do not have routine sex to produce children.

And this conclusion doesn't just apply to humans.In fact, compared to other primates, humans are pretty close to the "average" number of routine sexual intercourses except for one offspring.Humans may also be ashamed of how much we have sex compared to chimpanzees, who spend almost all their time having sex.In addition to primates, lions may also dwarf humans, because lions must have sex 3,000 times to produce 1 offspring.As far as birds are concerned, some birds need only a few sexual intercourses to give birth to chicks, while others need hundreds of sexual intercourses to produce offspring.So why do humans and these animals need to have so much intercourse if not for reproduction?What role does routine intercourse play in the pursuit of reproductive success for both sexes?

The most common answer to the above question is that humans engage in sexual intercourse because it brings pleasure to humans (and perhaps other animals as well).But is that really the case?Now let's take a look at the couple in the scene.Of course, in the first few weeks of their partnership, they also had periods of daily sex.During that time, intercourse, physical contact, and even the expectation of nudity can turn them on.For this couple, after the initial excitement, they did get real pleasure from intercourse.Recently, however, the couple has not been as excited about intercourse as they used to be.As we see in the scene, the two are not looking forward to sex so much now.If they're both honest with each other, in fact, neither of them gets as much pleasure from intercourse as they did in the first place.

Judging from the description in the scene, the woman did not get any pleasure from sexual intercourse at all.For her, the whole process of intercourse was uncomfortable, even painful, and felt like it wasn't worth the extra effort.A woman doesn't get as much sexual arousal from having sex on a Saturday as she does from flirting with another man on a Wednesday.As for the man in the scene, he's been feeling edgy and bored throughout the foreplay.All he wanted was to penetrate his partner's not-so-wet pussy quickly, and while the man was pumping back and forth, they were both bored and eagerly waiting for the woman to get aroused.Men get a brief moment of euphoria in the seconds before ejaculation, but then immediately sink into the depression of guilt.And more importantly, not only did the couple get no pleasure from intercourse, the two of them knew what the outcome would be before they started intercourse.

So why were they having sex that Saturday night?And why keep having sex over and over again for years to come, every month, every week? In general, routine sex is exactly what it sounds like, a routine.Whether or not the human brain can figure out why, the bodies of both men and women are programmed to have sex with their mates on a regular basis.So why do humans have routine sex?Because routine sexual intercourse affects the number and quality of human offspring and offspring.Although human beings have to have more than 500 sexual intercourses to conceive once, so although routine sexual intercourse is not under the conscious control of the brain, routine sexual intercourse does affect the quality of human offspring. So, what is the greatest benefit to human beings from this kind of routine sexual intercourse that is not controlled by the brain consciousness?Men and women gave different answers to this question.At the same time, this is the first example that illustrates the theme of this book.In other words, the theme we are trying to address in this book is that what one partner considers to be the optimal strategy is often not the optimal strategy for the other half.Take this scenario, where the man's body is trying to maintain its own sperm count in the mate, but the woman's body, both consciously and subconsciously, is trying to mess with the man and try to keep him from timing his ejaculation optimally. Many primate females, such as orangutans and baboons, exhibit self-promotional behavior during the most fertile times of the month.At this time, the area around the anus and vulva of the female orangutan or baboon will become red and shiny, and even swell, and sometimes even their chests will also turn red, and the male orangutan or baboon will feel the changes when they see these changes. Very excited.When the red part of the female orangutan or female baboon is the most beautiful, the male orangutan and male baboon will try to have sex with her.During the days when a female orangutan or baboon is most fertile, several male orangutans or baboons must engage in fierce competition for their own purposes.Each male orangutan or baboon will do everything possible to keep others of his sex away from his target.Sometimes, they even give up eating in order to look after their goals. In contrast, many other primates, especially those that are monogamous (such as humans and gibbons), hide various signs of conception.Why is this?We can explain it this way: If a man doesn't know when a woman is most fertile, he can't keep her under intensive watch.Because for a man, it is impossible for him to watch over his object forever without sleep or food.For women, concealing the period of pregnancy can give her more initiative to decide when and with whom to conceive.Especially when a woman wishes to have an affair, concealing her fertile period can make it easier for a woman to deceive her spouse.And similarly, female gibbons conceal their fertile days in the same way. We can't help but be amazed by the ingenuity and efficiency of women's ability to conceal their fertile days.A woman's body is able to prepare a state that is conducive to conception, and when the time is exactly right, she can conceive immediately. On the other hand, a woman's body will never allow a man to find out the correct time of conception.To be honest, this reproductive strategy of females to disrupt males' ability to detect when to conceive is truly amazing. Let us explain in detail below.First, in general, a man's sperm can only survive for five days at most after entering a woman's body; second, it seems that it takes two days for sperm to reach the most suitable state for fertilization in a woman's body; Only one egg is released in a menstrual cycle, and the egg dies within a day of being released from the ovary.To sum up, if a man wants to fertilize a woman, he must ejaculate at least once in the woman's body during the period from five days before ovulation to 12 hours after ovulation.And if a man wants to have a better chance of fertilization, although the probability is not high (about one in three), he must ejaculate inside the woman two days before she ovulates.During the period from five days before ovulation to 12 hours after ovulation, if the timing of male ejaculation is slightly wrong, the chance of female fertilization will be significantly reduced. From this point of view, it seems that all men should carefully record the date of each partner's menstrual start.Because, as long as you know the time when menstruation begins, a man can ejaculate in his partner on the 12th day after menstruation begins.And two days later, it happened to be the time when his sperm was most suitable for fertilization, and it happened to be the 14th day after the start of the spouse's menstruation. We usually assume that this is the fertile period for women.But is a woman's body really that simple to predict with this algorithm?In fact, the menstrual cycle of ordinary women seldom starts according to the scheduled time, and very few women really ovulate on the 14th day after the start of menstruation.And this variability is the focus of women's reproductive strategies.Moreover, due to this variability, we cannot predict the reproductive strategy of females at all. Usually, a female's menstrual cycle (that is, between the beginning of this menstruation and the beginning of the next menstruation) is about from 14 days to 42 days.This variation in cycle length is not only due to individual differences between women, but also for the same woman, the length of her menstrual cycle is not exactly the same every month.The most flexible part of each menstrual cycle is the length of the period from the beginning of menstruation to ovulation. In other words, this period happens to be the most important part for men.A normal and healthy woman not only will not ovulate exactly on the 14th day after the start of menstruation, but her ovulation day may even stretch from the 4th day to the 28th day after the start of menstruation.Regardless of whether it is a man or a woman, it is impossible to predict the most fertile time of a woman if the date of the woman's last menstrual period is used to calculate. Of course, it takes more than a change in ovulation for a female to prevent her mate from finding out when she's fertile.Because if you don't look at the changes in ovulation, women will show more interest in sexual intercourse during the most fertile period.This alone makes it easy for a man to see that she is fertile.Usually, women always show some complex and false emotions and behaviors unconsciously, the main reason is to confuse men to find out whether they are in the fertile period.For example, first, whether a woman is fertile or not, her body is always ready to receive internal ejaculation from her partner throughout the menstrual cycle; second, a woman's body is often in an ambiguous state throughout the menstrual cycle , it is difficult for men to recognize whether a woman's interest in sexual intercourse is real, fake, or optional.In this way, even when a woman expresses interest in intercourse during the most fertile days or two, men cannot distinguish it from faking interest.And there's a more subtle part of a woman's reproductive strategy, which is that even the woman herself can't figure out when her fertile period is.It is also because of this that women can prevent their spouses from finding out when they are most suitable for conception.As far as women's reproductive strategies are concerned, their inability to consciously know when they are most fertile is not in itself accidental, but is as important as other elements of female reproductive strategies. Precisely because women's reproductive strategies are so wonderful and effective, men cannot estimate the best timing for ejaculation in front of women's reproductive strategies.But men also have a subconscious coping strategy: trying to keep their sperm in their mates.From this point of view, routine sexual intercourse can just bring benefits to both men and women.If a man can keep ejaculating in his spouse every two or three days, his sperm should be available in his spouse at any time.In this scenario, a man is one in three more likely to impregnate his mate each month.As long as the timing of an ejaculation is wrong, his spouse cannot conceive.Such is the case with the couple introduced in this scene. The scene in which the man ejaculates his spouse every time is on a Saturday.And his last ejaculation was a week ago, which means that the sperm he last ejaculated into his partner had all lost their ability to fertilize last Wednesday.The man's partner ovulates on Thursday night, and although the woman's eggs are alive until Friday, and some viable sperm enter her body, these sperm have long since lost the ability to fertilize.The woman's sexual intercourse did not make her pregnant.Her next menstrual cycle will start over in two weeks.And, her next period will most likely start on Saturday, two weeks from now.We can predict with such confidence here when her next period will start primarily because we were able to correctly estimate the number of days between ovulation and the start of her next period.Usually this period should be 14 days, even if it is slightly stretched, it will be between 13 and 16 days. When the woman's next period begins, the couple will find that their month's efforts have been wasted again.However, for this result, we can also explain it from another angle: in fact, this month is a woman's body that cleverly and actively avoids pregnancy.At least she avoided having her spouse impregnate her. We mentioned earlier that a woman can prevent a man from finding out when she is fertile by asking or allowing intercourse with him during the menstrual cycle.But that's not entirely accurate.Because throughout the menstrual cycle, women's attitudes towards routine sexual intercourse also undergo some subtle changes. First of all, neither men nor women feel much desire to have sexual intercourse during menstruation.Some human societies even consider sexual intercourse during menstruation a taboo.And for other primates who have sex throughout the menstrual cycle, they also, like humans, reduce the frequency of intercourse during menstruation.Even animals that don't bleed during menstruation, like marmosets. Second, women are more likely to have routine intercourse in the two weeks following ovulation.This might come as a surprise, because during the time when a woman is most likely to have sex (the first two weeks after ovulation) she is unlikely to conceive.And during the period when a woman is likely to conceive (the two weeks before ovulation), her "sexual" interest is not very high.The gap mentioned here, although we can use statistics to prove it, but because this gap is so subtle, usually both men and women have never noticed this phenomenon.Moreover, this subtle change in behavior from routine intercourse was not the result of a conscious desire by either man or woman to avoid pregnancy.This is true even in women who are using fairly reliable methods of contraception, such as the pill.And the same is true for other primates.In other words, women's subtle changes in sexual intercourse at different times are mainly affected by hormone secretion, rather than brain control. Taken together, women's bodies are able to subtly manipulate "when" or "how often" they have sex, and this is just one of the ways women can manipulate their mate's chances of fertilization.There is another way for a woman's body to control whether it accepts her mate's sperm in whole or in part.Most people have never noticed the dampness left on the sheets after sex, let alone marveled at the amazing and delicate power of the female body.For this, we will explain it in the next scene.I hope that after reading the next scene, the tide on the bed sheet after sex will not be the same as before.