It could be a mortal man who somehow managed to catch Artemis's eye. Maybe he was a great hunter like her, and their brief encounter led to the pregnancy.
One idea could be that Artemis has to face unexpected challenges during the birth. Maybe there are threats to the baby from some mythical creatures who see the new life as a potential future enemy. Another could be that the other gods and goddesses react in different ways, some with envy and some with joy.
It would be complex. Artemis, as his mother, would likely be protective yet conflicted. She has her own identity as a virgin goddess, and Percy's existence challenges that. But she would also love him deeply. Percy would probably look up to her and be in awe of her powers, yet also struggle with the fact that his mother is such an unusual figure in the mythological world. There might be a sense of distance at times because of Artemis's nature, but also an unbreakable bond.
One possibility could be a very unorthodox take on the mythological world. Maybe it involves some powerful magic or a strange prophecy that defies the normal rules. Artemis, being a virgin goddess in the original mythology, giving birth would be a huge deviation. It could start with some sort of interference from a powerful and dark force that manipulates events to make this happen. Percy might then grow up with a unique set of powers and a connection to both Artemis and his own demigod heritage in ways that are completely different from the normal Percy Jackson stories.
I'm not sure specifically as I haven't read that particular fanfic. It could be about Betty's experience during childbirth, perhaps the emotions she goes through, the people around her at that time, and how it changes her life.
Obviously, Ana herself would be the central character. Her partner could be an important character too, being there for her during the pregnancy and birth. Maybe her mother or a close female friend who offers advice and support.
The fanfic might focus on the actual birth. It could describe the setting, whether it's in a hospital or at home. And also the people around her during the birth, such as a midwife or her partner. There could be some tense moments and then the joy of the new life arriving.
Well, it could be about the challenges Clary faces during childbirth, like her fear and the support she gets from her friends. Maybe her partner is by her side, holding her hand through the pain.
One common theme could be the development of family relationships. When the reader gives birth, it often leads to the exploration of how the new family dynamic works, like the relationship between the reader and the partner in the fanfic, and also how they raise the child together.
There's also the possibility that it's an unknown stallion from a far - off land. Twilight could have had an adventure in a different region and met someone there. This would add an element of mystery to the fanfic, as the readers would be curious to learn more about the father's background and how he and Twilight met.