It could be that the girl is a young scientist who accidentally creates a device that inflates the boy while she was conducting an experiment. In this case, the boy could be her assistant or just an unlucky bystander. And they both have to figure out how to fix the situation.
The girl could be a magical being from another realm, and the boy could be a normal human. Her powers are not fully understood, and when she inflates the boy, it sets off a chain of events that involve other characters from both her realm and the human world, all trying to understand and resolve this strange occurrence.
It could be a symbolic story. The 'inflating' might not be literal but represent how the girl's actions or words cause the boy to grow in confidence or ego, inflating his self - perception in some way. For example, if the girl constantly praises the boy, he starts to feel more important and 'inflated'.
The main characters could be a high - school girl and boy. The girl might be a popular one who likes to bully the less popular boy.
The girl could be a young athlete and the boy could be her rival in a sports event. She has more determination and thus beats him.
Obviously, the main characters are the boy and the girl. But we don't know their names or much about them without more of the story.
The main characters are obviously the girl and the boy.
The main characters are, as the title suggests, the girl and the boy.
Obviously, the main characters are the boy and the girl.
The main characters could be a nerdy 'cherry boy' who is always buried in his books and a sporty girl. The boy might be really smart in academics but lacks social skills. The girl, on the other hand, is confident on the sports field but not so good in studies. They could help each other out, with the boy tutoring the girl and the girl teaching the boy how to be more confident in social situations.
The main character could be a tomboyish girl named Lily. She's always been interested in things that boys usually like, so she's excited to be in the boy camp. And then there could be a boy named Jake, who is initially suspicious of Lily but later becomes her best friend.
Well, clearly the girl and the boy are the main characters.