One reason could be for spiritual comfort. Jail is a tough place, and reciting the Quran can provide him with a sense of peace and connection to his faith.
It might be that he has a lot of time in jail to reflect on his life and the Quran offers him guidance. He may be seeking answers from the religious text for the situation he is in, or he could be using the recitation as a form of meditation to deal with the stress and isolation of being in jail.
I'm not sure about a specific story of a boy reciting Quran in jail. There could be various individual cases or fictional tales related to this. It might be that the boy was in jail for some unjust reason and found solace in reciting the Quran.
One possible reason could be that he's been framed for a crime he didn't commit. Maybe some powerful enemy managed to plant false evidence against him. For example, they could have made it seem like he attacked a village or stole a powerful artifact.
One reason could be lack of female friends or relatives. If the bride doesn't have many suitable female options, she might turn to a close male friend or relative like a boy.
Another reason might be as a form of self - exploration. Boys may want to understand what it's like to be in the shoes (or rather, the high heels) of the opposite gender, explore different aspects of identity, or simply break free from the traditional gender norms.
One possible reason is her acts of violence. Callisto was often on a warpath, attacking villages and people. So, her criminal actions could have led to her imprisonment.
One possible reason could be that he's framed for a crime he didn't commit. Maybe someone powerful wants to get rid of him and plants false evidence. For example, they could make it seem like he attacked a village ally when in fact he was defending it from a hidden enemy.
One possible reason could be that he's framed for a crime he didn't commit. Maybe some powerful enemy manipulates evidence to make it seem like Naruto has attacked a village or something. Another reason could be that he breaks some strict laws while trying to protect someone. For example, if there are laws against using certain powerful jutsus in a populated area and he does it to save a friend, he might end up in jail.
One possible reason could be revenge. Maybe the girl felt wronged by the boy or his family in some way and decided to kidnap him as payback.
Magic could be a reason. Like in a fairytale world, a magic spell or a magic object might cause the transformation. For example, a magical amulet that when activated changes the boy's gender.
One reason could be bullying at school. Other kids might pick on him because he's different in some way, like being too shy or having an unusual hobby. This can make him feel really sad and isolated.