There may be a partner of the impregnated person. This character could be in denial, or trying to support in a difficult situation. Another character could be a mysterious figure, like a witch or a seer who has some premonition or knowledge about the monster baby. And there are usually bystanders or other members of the community who react to the impregnated person in different ways, either with fear, disgust or pity.
A theme could be the battle between good and evil within the context of the pregnancy. The impregnated person may struggle with whether to keep or get rid of the monster baby, representing the fight between what society deems right and the unknown potential of the baby. And there's often a sense of isolation, as this is not a normal pregnancy that others can easily understand.
There's the monster, of course. It could be a big, hulking creature like a werewolf or a more mysterious one like a vampire. Then there are the humans who misunderstand it. There might be a hero figure who eventually realizes the truth about the monster, like a brave knight or a clever detective. And there are often bystanders, ordinary people who are afraid of the monster without really knowing it.
Typically, the main characters in a secret baby story are the mother, who holds the secret of the baby. She is likely to be a complex character, dealing with the guilt, love for the child, and the fear of revealing the truth. The father, who is in the dark about the baby, and when he finds out, his world is turned upside down. And the baby, who is innocent but whose presence has a huge impact on the lives of the adults around it. There could also be side characters like friends or family members who might later get involved when the secret starts to unfold.
Typical characters include the main monster protagonist. There could be a human love interest, adding an element of inter - species relationship. And don't forget about the antagonists, which could be hunters or other malevolent monsters. Also, there might be sidekick characters, like a small, friendly creature that accompanies the monster on its journey.
Well, the billionaire is obviously a key character. They are usually portrayed as powerful, often controlling, and living a luxurious life. There's also the baby, of course, who can be either a normal, cute baby or have some sort of special quality or power. Then there are usually the nanny or caretaker characters. They can be kind - hearted and play an important role in the baby's upbringing. Sometimes, there are rivals to the billionaire, like other business moguls who might see the baby as a threat to their own interests or a way to get at the billionaire.
In some fanfictions, there could be a wise old animal, perhaps an old elephant or a hermit-like fox, who gives advice to the baby tigress. And sometimes, there are other young animals of different species that the baby tigress befriends or has conflicts with. These characters help to build a more complex and interesting world around the baby tigress.
Typically, there's the kidnapped character who is the main focus. Then there's the kidnapper, who can be a complex character with various motives. There might also be side characters like other captives or people who are trying to rescue the kidnapped one.
Often, it's the curious ones. People who venture into unknown areas without fully understanding the risks. Like explorers in a jungle where a giant snake monster lives.
Often, it's an ordinary person. Maybe a scientist who experiments on themselves and accidentally turns into a monster. Or it could be a young, curious individual who stumbles upon something that causes the transformation.
Often, the monster itself is the protagonist. It goes through the process of reincarnation and all the adventures and challenges that come with it.