Living beings continue to evolve. Every evolutionary step must create an advantage. Every tiny step from fish to man was an advantage. No living being can develop a characteristic if the intermediate steps towards this characteristic are useless or obstructive for the living being. This is true for all living beings - for all living beings except one.
Night fairies copy DNA. Night fairies copy genes. Night fairies have adapted to copy the adaptations of other living beings. That is a theory.
Based on physical characteristics, one could assume that night fairies evolved from a human species, but there is more evidence that they were initially coleoidea (squid, octopus, cuttlefish). Night fairies have ANA. Very few beings have ANA. They are exclusively soft-bodied beings, such as some snails and coleoidea. It is remarkable that these living beings developed completely independently of all other life. They could have existed before the first plants grew on the planet.
If one were to try to add night fairies to the tree of life, they would potentially be something like the opposite of the origin. They have characteristics of several living beings combined. But they have hardly any characteristics of coleoidea, apart from the ANA. An coleoidea is a soft-bodied being without bones. The tentacles of coleoidea are covered with suction cups. The tentacles of a night fairy have bones and joints, but no suction cups. Night fairies are therefore something else or have become something else. They are not soft-bodied beings, but they still have ANA.
DNA and RNA are not well understood. ANA is not understood at all. It is unclear whether ANA gives night fairies the ability to mate with beings of other species, because the corresponding soft-bodied beings do not. It is possible that night fairies have decoded this ability for themselves through many mutations, but it may also be through other means.
ANA and DNA are similar. The structure is similar, but ANA is more stable. It is a different sugar. The sugar is aliose. Some of the bases are different. DNA has four bases and two possible base pairs. ANA has six bases and three possible base pairs. The information density should be higher. It is not possible to say how much higher. Nor is it possible to say how many base pairs and genes a night fairy has. Even with for living beings with DNA, it is impossible to say for sure, and where it is possible to say, it is often only a rough estimate.
A night fairy has 24 chromosomes and 2 sets of them. One estimate says: Compared to humans, night fairies have fewer base pairs and more genes.
In the whole world there is only one laboratory in Tor that is actively researching ANA, so there will probably not be any more precise estimates for a long time.
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Sperm cells are attracted to an egg cell, but it is not a real egg cell. It is a mock egg cell. It is a platina cell. It is a different platina cell depending on the type of sperm cell. A night fairy has millions of such cells. Many of them are ready to receive sperm cells at the same time. Which ones is coordinated with other bodily functions, such as the production of bodily fluids, like sexual secretions and sweat. No sperm will ever fertilize the real egg of a night fairy. Usually there won't even be one. The platina cell is also not really fertilized by the sperm cell. The sperm penetrates, but then it is broken down. The DNA is translated into ANA and replicated. Large parts of the DNA are discarded. The rest is incorporated by the platina cell into its ANA and only then does meiosis take place. In the end, there will be four pseudo-sperm cells with different ANA. Platina cells are spheres. The pseudo-sperm cells are spheres with tails. One or more mature egg cells enter the fallopian tube at a nearby point in time and thus become accessible to the pseudo-sperm cells. The pseudo-sperm cells are attracted to the egg cell. A pseudo-sperm cell will fertilize the egg cell.
Night fairies are not hermaphrodites. Without a foreign sperm cell, a platina cell cannot divide into pseudo-sperm cells.
It is not clear how the platina cell knows which parts of the DNA fulfill which purpose.
The ANA of a night fairy contains comprehensive information about the structure of the DNA of other living beings. That would be a reasonably logical consequence, but it seems unrealistic. The amount of information would have to be enormous, but it doesn't look like it. It could be that ANA is highly compressed and only decompressed when a section is really needed, but it is impossible to say. It could be that it only contains information about coded DNA of certain living beings, because uncoded DNA serves no purpose, but that can't be said either. The problem is that DNA is not understood well enough to even begin to understand how this process works.
One might assume that there must be great differences between night fairies because individuals reproduce with distinct living beings, but the opposite is the case. Night fairies always look very similar. There are not many possibilities as to why this could be the case. All night fairies could be descended from a single specimen from the recent past. The possibilities for evolution could be severely limited. More DNA could be discarded than it appears. It could be that DNA is only incorporated into uncoded ANA. It could be that night fairies do exchange genetic material with each other in some way and at some interval. Any or all of these points could be true.
A platina cell cannot penetrate an egg cell, but it would be possible for night fairies to exchange the pseudo-sperm cells with each other in some way. They would also combine large parts of their ANA in this way. Such an interaction between two or more night fairies has never been observed, however, night fairies are not well studied.
A last possibility would be that there were or are male night fairies after all, but there are many arguments against this.
So the concluding answer to the opening question is: It's a mystery to science.
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