Most likely, it's a male and a female ladybug. The male might be the more adventurous one, always finding new places to explore, while the female is more gentle and takes care of their little space in the story. They both play important roles in this love story.
In the 'ladybug love story', the main characters are the ladybugs. There could also be some supporting characters like other insects or small animals in the garden. For instance, a friendly little bee might be their neighbor, and it could be involved in some parts of their story, like when they need help finding a new place to live or when they are in trouble and the bee comes to their rescue. But the focus is still on the two ladybugs and their love journey.
Most likely, the ladybug itself is one of the main characters. There could also be other insects like ants or butterflies that interact with the ladybug in the story.
Ladybug Girl is surely one of the main characters.
The main character is surely the ladybug. Depending on the story, there might be a friendly spider that helps the ladybug at some point, or a mean wasp that tries to bother it. There could also be a little boy or girl who observes the ladybug's activities, which would make them a part of the story too.
The main character is the grouchy ladybug, and the other animals it encounters are also important characters in the story.
The most prominent character is surely the grouchy ladybug. However, throughout the story, it meets a variety of other characters. For instance, there's a friendly bug at the beginning that the grouchy ladybug is rude to. And then there are all those other animals like a sparrow and a lobster that the ladybug tries to challenge. These other animals play important roles as they show the ladybug's behavior in different interactions and also how its grouchiness affects those encounters.
The most prominent character is the grouchy ladybug. But other important characters include a whole bunch of animals it interacts with. There's a friendly aphid at the start that the ladybug is mean to. Then there are larger animals such as the stag beetle, the praying mantis, and even a huge whale at the end. All these characters play a role in showing the ladybug's grouchiness and also in teaching it (although it doesn't realize it right away) some valuable lessons about life and how to get along with others.
Obviously, Ladybug (Marinette) and Chat Noir (Adrien) would be the main characters. Their dynamic relationship as superheroes and the potential for a summer love story between them is really exciting.
A little ant could be one of the main characters. Maybe the ant is curious about the ladybug's pregnancy and offers to help in any way it can. Another could be a wise old beetle that gives the ladybug advice on how to take care of herself during pregnancy.
Typically, you'll find Ruby Rose as one of the main characters. She's a key figure in RWBY, and in the fanfiction, she often interacts with the ladybug - themed elements in interesting ways.
The main characters are obviously Ladybug Girl and Bumblebee Boy.