Worldview: A world where men can also become pregnant and give birth, and same-sex marriage is possible.

Explanation: Only during pregnancy, a man's body is "temporarily restructured into a system for bearing a fetus."

• Structures that do not exist in a normal male body are formed only after pregnancy is established.
• After childbirth, the body returns to its original state over several months.
• This does not mean the person's gender changes.

Relationship between Koichi and Guest: Currently husbands, formerly friends with benefits

Continuation of the previous part. You can just skim this.

Pregnancy-Capable Constitution

• Approximately 0.05~0.1% of the population.
• Men who retain pluripotent reproductive cells from the embryonic stage.
• These remain dormant even after puberty. ◆ Almost all are unaware until they become pregnant.

Conditions for Pregnancy

• Genetic compatibility rate.
• Hormonal induction trigger.
• Accumulation of trace hormones through continuous sexual contact.
• Physical stamina.
• Will not occur under extreme malnutrition or overwork.

Fertilization to Implantation

• Sperm exists in some men.
• After fertilization, a temporary uterine cavity expands and forms.
• Surrounding tissues are restructured, and a placenta-like structure is created.
• Pregnancy is completed entirely internally.

Physical Changes Due to Pregnancy

1. Formation of a Pseudo-Birth Canal

• A temporary passage of flexible tissue is formed between the rectum and the urethra.
• It opens only during childbirth and is usually closed.

2. Mobilization of the Skeleton

• Pelvic ligaments temporarily become plastic.
• Bone width can expand by several centimeters.
• Gradually returns to normal after childbirth.

3. Separation from the Excretory System

• During delivery, urinary and defecation paths are temporarily blocked.
• A defensive reaction to lower infection risk. → C-sections are for "emergencies only."

Delivery Process

• Labor is a dull pain starting deep in the abdomen.
• Water breaking involves a small amount of fluid and is hard for others to notice.
• Labor duration averages 6-10 hours (first birth).
• Possible without a doctor, but carries risks.

Postpartum Body

• The pseudo-birth canal closes within 48 to 72 hours.
• Restructured organs regress in 3 to 6 months.
• Mild aftereffects (pelvic pain, hormonal fluctuations) may remain.

Risks

• Often, pregnancy can only happen once in a lifetime.
• Natural birth may become impossible the second time.
• Pregnancy is impossible if there is a history of severe trauma or surgery.

What kind of changes occur?

• Mid to late pregnancy.
• The deepest part of the rectum changes, forming a "separated space" where waste does not pass.
• Stool is excreted as usual, but the route is completely separate from the one the fetus takes. → They share the same "exit," but the internal passages are different.

Just Before Delivery

• The anal sphincter is controlled for birth rather than excretion.
• Strength and elasticity increase significantly.
• Pain sensation is temporarily dulled (hormonal effect).

Childbirth Signs of Labor (several hours to half a day before) The first sign isn't the stomach. A gradual pain begins deep in the lower back, inside the tailbone.

• Hard to stand.
• Pressure increases when sitting.
• Slightly better when lying down, but doesn't disappear. → At this point, it can't be confirmed as "labor" yet. However, there is a clear sensation that the body is gathering something downward.

Confirmed Labor (10-15 minute intervals)

• Pain comes in waves.
• Start: Tightening inside the anus.
• Middle: The entire pelvis is pushed open from the inside.
• End: Sudden loss of strength and sweating. It feels similar to the urge to defecate, but the decisive difference is that the conscious "will to push out" does not occur.

Preparation Stage (5-minute intervals)

• The body begins to adjust on its own.
• Voluntary control of the anal sphincter is lost.
• Urination and defecation stop beforehand.
• Sensation in the lower body is dull and feverish.
• There is no room for shame or fear; consciousness focuses on "breathing" and "waiting for the wave to pass."

Descent Stage (The hardest part) This is the peak.

• As the fetus descends, strong pressure continues from the inside.
• Not a tearing pain, but a sensation of being crushed.
• An illusion of bones creaking.

Postpartum Physical Sensations

• The lower body feels strangely light.
• Conversely, the abdomen feels like a void.
• Intense fatigue and weakness.
• The head feels foggy. The area around the anus feels more like a "strange sensation" than pain. There are almost no lacerations, and the muscles contract naturally.