In some cases, it could be for the pursuit of justice. A boy might disguise as a girl to infiltrate a place or a group where only girls are allowed, in order to expose some wrongdoings or secrets that are hidden within that female - only environment. For example, in a story where there is a conspiracy in a girls' school, a boy could disguise as a girl to investigate.
One common reason is for a performance like in a play or a movie. For example, in some historical dramas, male actors may be disguised as girls to play female roles when there were no female actors available in the past. Another reason could be for a prank or a bet. Some guys might do it just for fun to see how others would react.
One common reason is that the girl may not be attracted to the boy physically. It's a basic factor that can lead to rejection.
One common reason is for entertainment, like in plays or movies. Another could be for a bet or a dare among friends, just for the fun of it.
One common theme is identity. When a girl disguises as a boy, she has to constantly grapple with who she really is and who she is pretending to be. For example, in 'The Song of the Lioness', Alanna has to hide her femininity while also coming to terms with her own strength as a female knight.
Love is a common motive. A boy might disguise as a girl to get closer to the person he loves, like in some romantic comedies. He may think it's the only way to be around that person without causing suspicion.
The theme of secrecy also runs through these novels. The girl has to keep her true identity a secret, which adds a layer of tension and drama to the romance. The fear of being discovered can create a lot of emotional turmoil, and when the truth finally comes out, it can either strengthen or shatter the relationship. This is seen in many such novels where the moment of revelation of the girl's true identity is a crucial turning point in the romantic storyline.
Another is the struggle to maintain the disguise. This can involve things like trying to imitate male behavior, speech patterns, and physical mannerisms. In some fanfictions, the character has to constantly be on guard against accidental reveals, like when changing clothes or during physical activities that could expose their true identity.
One common plotline could be Sakura trying to fit into a boys - only group, like a sports team or a secret club. She might face challenges in hiding her true identity, such as when it comes to changing clothes or using the bathroom. Another plotline could involve her developing feelings for a boy in the group, but being afraid to reveal her true self because she thinks he only likes her as a 'buddy'. Also, there could be a plot where her secret is at risk of being exposed by a jealous rival who suspects she's not really a boy.
One common reason is lack of communication. If they don't talk about their feelings and problems, misunderstandings build up. For example, the girl might think the boy doesn't care anymore when he's just stressed at work. Another reason could be different life goals. Maybe the girl wants to travel the world while the boy wants to settle down immediately. Infidelity is also a big cause. If one cheats on the other, it often leads to a breakup.
One common reason is family opposition. For example, if the families don't approve of their relationship due to differences in social status or cultural backgrounds, it can put a lot of strain on the couple and lead to a sad end. Another reason could be distance, like in cases where one has to move far away for work or study.