Another idea is that it's part of a magical experiment. Harry volunteers for an experiment that he thought was about enhancing magical abilities, but it goes awry. He then has to deal with the impending birth of kittens. The story could focus on his attempts to find a way to stop it or accept it and the moral dilemmas that come with it.
One plot idea could be that Harry is cursed by a dark wizard. The curse is designed to humiliate him by making him go through an unusual form of 'pregnancy'. As he nears the time to give birth, he discovers that the kittens have some special powers that could be used either for good or bad, depending on how they are raised.
One idea could be that Harry discovers he has a magical ability that allows him to give birth to kittens as a form of new magic. The kittens could have special powers and Harry has to protect them from those who want to use the kittens for evil.
Harry could be developed as a more nurturing character. Since he has to take care of the kittens, he shows a side of himself that is gentle and patient, which is different from his usual heroic self.
One possible plot could be that Harry is part of an experiment in a fictional world. The experimenters are trying to combine different species' abilities, and somehow Harry ends up being the subject that gives birth to kittens. It could then be about his journey of dealing with this new situation, taking care of the kittens, and facing the reactions of the people around him in that fictional world. This might involve him learning about the kittens' special powers or needs, and also dealing with the social implications of such an unorthodox event.
Another idea might be the nature of the cubs. Are they part human, part magical creature? And how do they inherit Harry's traits and powers? This could lead to many adventures as Harry raises them.
Perhaps in this fanfic, Harry's pregnancy is a result of an ancient magic related to a deep emotional bond in their dating relationship. The story could revolve around how they balance their studies, their relationship, and the upcoming birth. They might seek help from a wise teacher who has knowledge of such rare magic.
In this fanfiction, perhaps it could lead to a whole new set of adventures for Harry Potter. He might have to raise these pups in a world full of dark magic threats, adding a new layer of challenges to his story. And it could also change his relationships with his friends, like Hermione and Ron, as they might have different opinions on this strange event.
One plot idea could be Mal facing challenges in adjusting to motherhood while still dealing with her past as a villain. Maybe she struggles to balance protecting her child from the dark side she once knew and teaching them about their unique heritage. Another could be the reactions of her friends from the Isle of the Lost and Auradon. Do they support her fully, or are there some who are skeptical? And a third idea is that the baby has some sort of special power that attracts both good and bad forces, forcing Mal to make difficult decisions to keep the baby safe.
Perhaps in the 'harry gives birth at dursleys fanfiction', there's a new form of magic introduced. Harry could have been affected by a magical experiment that causes this strange phenomenon. The Dursleys, who have always mistreated Harry, now have to face the consequences of having such a unique and unheard - of event happening in their house. They might be in a state of panic and confusion as they try to figure out what to do.
Perhaps the 'bro' is a place that has some special properties. Harry enters this 'bro' place, and due to the energy or magic there, he undergoes a transformation that leads to giving birth. The story could then be about Harry coming to terms with this new situation, dealing with the physical and emotional changes, and trying to find out how to reverse it or at least live with it.
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.