Breeding and Romance
This is a complicated pair of subjects that are only being sorted into a single chapter because humans link them together. Pokémon draw no links between sexuality and romance.
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Breeding
Debunking the rumors: Pokémon do not naturally engage in sexual behavior outside of mating season. There are stories of women and men being raped by a pack of Mightyena or being molested by a Tentacruel. These are examples of cruel, delinquent, or criminal Trainers deliberately teaching their Pokémon to behave like that, and then the Pokémon become feral through release or death of the trainer.
The game got breeding mostly correct. Most of the inconsistencies with reality are because of system limitations or player convenience. In the case of Nidorina and Nidoqueen, both can breed. Their inability in the games is a glitch that never got fixed.
All Pokémon lay eggs. Pokémon can be sorted into thirteen Egg Groups, with three special categories. Any two Pokémon within the same Egg Group can theoretically breed. The mother defines the species, while the father passes on Egg Moves (More on Egg Moves in the Moves Chapter).
All of this was covered in the games. Uncovered were details such as the fact that different Pokémon produce different types of eggs. An egg from a Totodile may be a hard shelled oval about a foot long from base to tip, but a Magicarp egg is a small, shell-less ball. Some eggs require special environmental equipment to incubate. Others need only to be kept warm. Some specific Pokémon can reproduce without eggs.
Further, some Pokémon cannot be made to breed even if in the same Egg Group. Examples include Zangoose and Seviper – which would try to kill each other on sight and eat the corpse – and male Corsala and female Mareanie/Toxapex (the inverse, male Mareanie/Toxapex and female Corsala has actually happened once on record and involved a delinquent trainer).
Pokémon also have fertility cycles. For some, this means they go into heat during the new moon. Others only mate during a period between late spring and early summer. Another species may tie their cycle to the blooming of a particular flower. There are too many mating cycles to describe here. Pokémon of the same Egg Group may not have cycles that mesh. Snorlax becomes fertile in the middle of spring, while Avalugg mates in early winter. Yet, both are part of the 'Monster' Egg Group. Part of the reason Breeders spend years studying is to learn the various methods to artificially coax a pair of Pokémon into heat at the same time.
The other reason for the League mandated certification tests for Breeders is to protect the health of the Pokémon involved. In the wild, female Syther eat their mates in the middle of the process. Female Mightyana have been known to leave their mates in need of a Pokémon Center due to severe bite wounds. Many Pokémon go through a period of recovery after breeding. In some cases, this recovery takes years, while others last months. Rattata may be able to produce more offspring on a monthly basis, but Nidoran require two years between breeding. Knowing how to prevent injuries and undue strain on both partners takes a large amount of training.
Most breeders are skilled trainers, at least as skilled as Gym Leaders, if only to be able to defend themselves from Pokémon that get aggressive during mating season or brooding over a nest.
Very few Pokémon have sex drives outside of mating season. During mating season, most will only focus their libido on others in their egg groups. The exceptions will be noted in the species entry in later volumes.
Newly hatched Pokémon may need days, if not weeks, of development before they are ready for even the gentlest of sparring matches. They may need months or years before they can breed.
The above details were too complicated and inconvenient for the games to use.
Special Groupings
Ditto belongs to the so-called 'Ditto Group'. Ditto can breed with any Egg Group. Word of warning: Ditto only goes into heat when it has maintained an accumulated energy store of more than 75% of its own body mass (relative to default form and mass (get default mass checked at a Pokémon center)) without burning off the excess calories (no battles or being used to travel or clear obstacles) for a span of two weeks, and is in the presence of a Pokémon in heat. Even then, it will not mate with something that needs substantially more calories than what its BMI would provide (mating with a high metabolism Pokémon will only occur if a much larger stockpile of calories is available). If one member of your team enters heat when Ditto has enough stored energy, be prepared for an egg or clutch of eggs. Several in some circumstances.
Some Pokémon have a weak evolutionary stage before their adult forms. These Baby Pokémon all lack the capacity to breed. Baby Pokémon usually evolve into a sexually mature form within a year of hatching. See below for the full list of Baby Stage Pokémon.
Pichu
Cleffa
Igglybuff
Togepi
Tyrouge
Smoochum
Elekid
Magby
Azurill
Wynaut
Budew
Chingling
Bonsly
Mime Jr.
Happiny
Munchlax
Riolu
Mantyke
The few Legendary Pokémon that have been captured by humans cannot be made to breed, with the exception of Phione and Manaphy, both of which can breed with Ditto to make a Phione Egg.
Due to its artificial origins at the hands of the Aether Foundation, Type: Null and its evolved form, Silvaly, cannot breed.
Ultra Beasts, being natives of the dimension known as Ultra Space, cannot breed as the environmental triggers needed only exist in the Twisted Darkness.
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Egg Groups and Basic Egg Care
For all the variety between different Pokémon and their breeding habits, Each Egg Group has certain basic rules for incubating an egg. Pokémon from more than one Egg Group have nesting habits that include aspects of both groups, though one is often more dominant than the other. Check which egg description is closer to the egg to see which is dominant.
Pokémon can lay eggs in clutches. Typically, lower evolutionary stages will lay smaller clutches, or even single eggs, while evolved Pokémon can lay substantially larger clutches. The average size of a clutch will be based on the highest evolutionary stages.
With species that fertilize the egg before laying it, there is usually a waiting period between fertilization and laying the egg. This period can range between hours and months, species dependent. Some varieties possess the capability to hold the fertilized eggs within their bodies until the eggs hatch, allowing for live birth, a process called ovoviviparity. It is not clear whether all such Pokémon can retain their eggs and simply choose not to, or if some cannot. Current research suggests that no Bug, Rock, or Steel type can retain their eggs for live birth (with the exception of Lucario), but more research is needed before anything is proven.
Without a League certification, it is technically illegal to sell a Pokémon egg or newly hatched Pokémon. That does not stop it from happening at a community level. Breeders make the bulk of their money by selling eggs or hatched Pokémon to trainers or distributors. Obviously, both supply and demand influence the prices, with something like a Pidgey egg or hatchling being cheap while an Eevee egg would sell for a tidy sum thanks to demand and rarity, and powerhouses sell for a fortune to the niche market of trainers with the skill to handle them. More information on the prices of eggs and hatched Pokémon can be found in the respective species entries.
Monster: eggs from this group are hard-shelled and fairly tough. A fully evolved specimen typically lays clutches of between five and twelve eggs, with clutches as small as one and as large as twenty recorded. The eggs tend to be buried in nests of earth, sand, burning coals, scrap metal, bones, or ice, or whatever else is appropriate for the species. The hatchlings dig themselves out. Live births have been recorded from this egg group.
Water 1: Most Pokémon in this group are also in another group. An egg from a pure Water 1 species will be small, transparent or translucent balls, numbering between dozens and hundreds. They need to be very moist, regularly supplied with water or covered in a moisturizing foam or mucus. Few from this group engage in live births.
Water 2: This is a small group. Most members of this group are completely aquatic. Clutches range from dozens to hundreds, with a few species laying over a thousand eggs in one clutch. The eggs are similar to Water 1, but require that they be completely submerged. How often the water must be refreshed varies. As the eggs are fertilized after being laid, live birth is not possible.
Water 3: Eggs in this group are laid in egg sacks that contain anywhere from one to a few dozen small eggs, with the number of egg sacs increasing as the number of eggs per sac decreases. The eggs are completely submerged in water during incubation. The eggs are laid and fertilized at the same time, preventing live birth.
Bug: These eggs are small, membranous balls. The sheer variety of incubation requirements and clutch sizes prevents a group-wide summary. Most Pokémon in this group are Bug type. Very few members of this group are also members of another group.
Flying: All members of this group have wings, and all but one are Flying type. The eggs are hard shelled, though more delicate than Monster group eggs. Eggs usually number between one and six, though up to ten is not unheard of. The nests are constructed and guarded by one or both parents. Some fill the nest with down to cushion and insulate the egg. A few live births have been documented in some members of this group that are in another group.
Field: Most members of this group have fur, none can fly, and all have been recorded with live birth. Between one and eight eggs is normal, with higher numbers almost unheard of. The eggs are hard shelled, kept in a nest, and fairly easy to take care of. Some breeders have designed incubators that have adjustable settings for all members of this group.
Fairy: Most, but not all, Fairy Types are in this group. The eggs are hard shelled. The peculiar feature of incubating these eggs is that they often hatch due to environmental triggers that are not related to time and temperature. They can lay dormant for decades before suddenly hatching when some arbitrary condition is met. Some hatch in the presence of certain emotions. Some need a thunderstorm. One even hatches due to tectonic activity.
Grass: these eggs have only medium toughness, but high constitution. More clearly, these eggs are more similar to seeds. Only moderate force is needed to damage the egg/seed, but much of the mass of the egg/seed is merely a reservoir of nutrients that are helpful, but not strictly necessary if planted right. These seeds usually need to be planted, partially or fully submerged in the right type of soil. They grow and sprout like a regular, non-Pokémon plant for some time. The Pokémon may eventually pop off the plant like a fruit from a tree. Alternatively, the whole plant may get up and walk away. There have been cases of these seeds being lost for decades, found, buried, and growing properly. Number of seeds, and methods of distribution, vary wildly. Some Grass Types actually want parts of their bodies to be eaten to distribute their eggs (Tropius's neck fruits are a prime example, though that is not the only way it can make and distribute seeds).
Mineral: These Pokémon are made partially or completely of some mineral structures. Half are genderless and can only be bred in captivity with Ditto. The eggs are oddly shaped and usually made of the same mineral structure as the Pokémon. Many are capable of lying dormant for centuries with no harmful effects. Usually, burying the egg in more of the mineral is required. The exact moment of fertilization is unknown, and none have shown live birth.
Amorphous: These eggs are usually soft shelled, but capable of squishing without harming the developing Pokémon, like a living stress ball. They can usually hatch with minimal support, though humidity control is needed with some. Live birth has been recorded, though it looks more like mitosis or budding.
Dragon: These eggs look like Monster Group eggs, but are much tougher. The shells have been known to survive automobile accidents, including one famous case of a Semi Truck going off a bridge with a trailer full of eggs for a Safari Zone, and anther involving a fuel tanker exploding. Clutches range anywhere between one and twenty. Some take over a year to hatch. Climate and nest are usually irrelevant, as these eggs can hatch whether they sat on a rock in a desert, in a puddle in a cave, or in a trainer's backpack. Live birth has been recorded when the mother feels too threatened to lay the eggs. Warning: some Pokémon do eat eggs, and Dragon Group eggs are often seen as both a delicacy and a challenge, given the difficulty of getting them away from their parents.
Human-Like: These eggs are similar to Monster Group eggs in form, though they have weaker, soft or semi-soft shells. Few Pokémon in this Group lay more than three eggs, and many only lay one per clutch. The eggs require careful tending. In this group, the mother or father will be fiercely protective of the egg, as they have collectively adopted the strategy of producing few young, but making sure that most survive to adulthood rather than playing the law of averages with lots of offspring. Live birth has been recorded in numerous cases.
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Romance
Love is a complicated subject even when it is only between two humans. Once Pokémon start adding themselves to the mix, it gets more tangled than Tangela. Case in point: Marriage between humans and Pokémon is illegal in Kanto and Sinnoh, and open romantic relationships are frowned upon in the Hoenn region. Johto and Kalos have made it legal (this issue is the heart of why Kanto and Johto are separate regions). Unova is generally accepting and has no laws for or against it – invoking the principle that if it is not explicitly illegal, it is legal – but it is considered polite to, in local vernacular, "get a room". Do not ask about the legality of marriage with Pokémon in Alola, as the laws became hopelessly tangled when the monarchy united all four islands and never became untangled.
Regardless of which Region you are in, it is entirely possible to have a romantic relationship with your Pokémon. There is no effective means to police that (though keeping romantic activities quiet in public is necessary in Kanto and Sinnoh). Marriage is the only thing that can be policed.
Most trainers with more than three years of experience can tell stories about a member of their team falling in love with another one. About half of those trainers can tell a story of a Pokémon falling in love with them.
Before going further, a specific point must be made. Pokémon have no connection between romance and mating. A pair may be deeply in love, yet will mate with other Pokémon come mating season. If you are dating your Pokémon, do not be surprised if your loved Pokémon needs to be taught about human sexuality and still goes off to breed come the season.
Dissuading an infatuated Pokémon without provoking an attack is a delicate business.
General advice:
1) Be observant and assess the depth of the emotions involved.
2) If it is merely infatuation, it can be dissuaded by gently explaining that you do not reciprocate. Make it clear that you care about the Pokémon as a friend and companion, but not a lover.
3) If it is more serious, explain your lack of interest, and then help the Pokémon through the heartbreak. Have the rest of your Pokémon offer support.
4) If it is deep and abiding love, you are in trouble. Not acknowledging the situation can only last for a while. Seeking out a romantic counselor could be required. Gym Leaders can also offer assistance.
Engaging in the relationship has its own difficulties
General advice:
1) Sit down with the Pokémon and discuss what both of you want out of such a relationship, and what limits need to be set.
2) If you have any intentions to include sexuality in the relationship, you will need to give the Pokémon a 'Talk'.
3) Remember that even small Pokémon can be dangerous and combine that knowledge with the old adage "Hell hath no fury like a woman (or Pokémon) scorned".
4) Research the social and breeding habits of a Pokémon to avoid misunderstandings, hurt feelings, accidents, and conflicts. Some Pokémon are polygamous. Others mate for life. A few Ghost types mate for death, which does not make any sense to the living, but does to the Ghosts (there is a reason that some Ghost type Pokémon are considered the best lovers in the world).
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Sex and Rape
The laws are clear. In regions where intimate relations are legal, consent is everything regardless of the intelligence of the Pokémon, and Baby Stage Pokémon are untouchable. Where romantic relationships are illegal, sex with Pokémon is likewise illegal.
That's it from the human-on-Pokémon angle.
From the Pokémon-on-human angle, things can get tricky, even ignoring the fact that policing wild Pokémon is nigh-impossible.
Again, Pokémon do not naturally engage in sexual behavior outside of mating season. One might if taught to by a human, but not otherwise.
During mating season is where things can get tricky. Some species have low libido, and thus will only act with their mate to produce offspring. Some seek out multiple mates, entire harems of partners in some cases, others using any available option, regardless of any degree of emotion between the two. Some species have males compete for the right to a female. Some species have the females fight over the male. Some fight their potential mates to test each other on relative reproductive fitness.
The ones that try to mate with multiple partners in one season by proving their strength to their potential partner are the dangerous ones to humans. The law of the wild is simple: Survival of the Fittest. If a wild Pokémon that pursues any available mate cannot find a mate for a while, and manages to defeat a creature that is not reproductively compatible, it may decide to seek some relief from the defeated target. As far as wild Pokémon are concerned, it is better to be used in such a manner than to be eaten/killed/left homeless. Beware being defeated by a Pokémon in heat. It is miles from civilization, and there are horror stories told by the survivors of such situations.
(thank you ChapterAquila92 on SpaceBattles for reminding me what the scientific term for producing eggs but gestating them inside the mother's body. I learned it when I visited the Zoo last summer, but forgot to give the actual term here.)
(I remember reading someone else's expanded pokedex, and the detail about it being 'better to be used than killed/eaten/driven away from home' came from them. Unfortunately, I cannot remember which pokedex fic it was. If you know, please alert me, so I can provide a link down here.)