A great plot could be that Alex discovers a long - lost spell book that contains spells that are considered forbidden in the wizard world. As she starts to explore the spells, she attracts the attention of an old and powerful wizard who wants to get his hands on the book. Alex then has to protect the book and herself while also deciding if she should use the powerful and dangerous spells.
Justin could be involved. He might be the one who either tries to help Alex get out of the forced lemon situation or, on the contrary, he could be the one who thinks she should just follow the rules. Another character could be Harper. She might be there to provide some comic relief while Alex is dealing with the lemon thing. For example, she could make jokes about Alex smelling like lemons all the time.
A magical detective who is investigating some strange magical occurrences in the neighborhood that Alex gets involved in. This character could be really serious and by - the - book, which would contrast with Alex's more carefree nature.
Since I don't know the specific story, Alex is probably the main character. He's a boy who has a connection to drumming, which is the central focus of the story.
Another storyline might be a time - travel one. They accidentally travel back in time and have to blend in with the past while also trying not to change history too much. During this, their feelings for each other start to change from just sibling - like to something more romantic.
I'm not sure who exactly Alex Cooper in 'The Real Alex Cooper Story' is without more context. It could be an ordinary person with a unique story, or perhaps someone involved in a particular event or field.
Alex would probably be both scared and defiant at first. He's a brave kid, so he'd likely try to find a way to escape right away. He might also try to talk his way out, using his intelligence to reason with Yassen.
In the fanfic, perhaps there's a spell gone wrong that forces Alex to be around lemons all the time. It could be that an enemy wizard casts a spell that makes her have an aversion to lemons but at the same time be constantly in their presence. So she has to figure out how to break the spell while dealing with the annoyance of the forced lemon situation.