In developing these characters, we can show Cho's jealousy in different ways. She might be passive - aggressive at first, like making snide remarks about Ginny. This would show her immaturity. Harry can be developed by having him be patient with Cho, which shows his good nature. But also, he should be shown as being very protective of Ginny. Ginny could be developed by having her reach out to Cho in a friendly way, trying to understand her jealousy. This would show Ginny's big - heartedness and could lead to Cho's character development as she realizes Ginny isn't a threat and starts to work on her own self - worth.
In some fanfictions, the plot might be that Cho is jealous because Harry seems so much happier with Ginny. She starts to follow them around, not in a creepy way but more out of curiosity and envy. As she does this, she discovers things about their relationship that make her both jealous and a bit sad. For instance, she might see Harry giving Ginny a special gift that he never gave to her. This could lead to Cho having an internal struggle about her own feelings and how to move on.
Ginny would likely be heartbroken. She's a strong character but she loves Harry deeply. She might start to question herself and what she did wrong. Cho, on the other hand, would be surprised but also happy. She may have still had feelings for Harry all along. Harry himself would be conflicted at first, feeling guilty for leaving Ginny but also excited about the possibility with Cho.
She might act overly friendly with other guys. For instance, she could be really touchy - feely with them, like hugging them a bit too long or playfully hitting their arms. This would make Harry jealous as he wants her attention all to himself.
In this type of fanfiction, Ginny's jealousy could stem from a few factors. First, Ginny has always been protective of Harry. If she senses that Draco, who has a history of being a bit of a bully and on the opposite side in the past, is getting involved with Harry, she might be jealous. It could also be that she's jealous of the new dynamic between Harry and Draco. Maybe they are solving mysteries together or having adventures without her. Ginny is a strong - willed character, and seeing Harry share things with Draco that she feels she should be part of could easily make her jealous.
They can start by sharing their experiences during the time they were apart. For example, Harry can tell Ginny about the challenges he faced in his travels, and Ginny can share how she has been growing as a person. This sharing can deepen their understanding of each other.
Harry is often developed as a conflicted character. He has the power of the Dark Lord, which brings out his more aggressive and power - hungry side, but deep down, his old self still exists. Ginny, on the other hand, is usually shown as strong - willed. She refuses to give up on Harry and is determined to bring out the good in him. For example, she might constantly remind him of their past and the values he once held.
Friendship is another theme. Stories often show how Ginny and Cho can overcome their initial rivalry and become friends. For example, they might bond over their shared experiences in the wizarding world or their mutual care for Harry in a more platonic way. This theme helps to add depth to their characters.
One popular 'Harry jealous of Ginny' fanfiction is 'Jealousy's Sting' on FanFiction.net. It delves into the insecurities Harry feels when he sees Ginny getting close to other guys. The author does a great job of portraying Harry's complex emotions and how it affects his relationship with Ginny.
They could develop their relationship through a shared dance. The physical closeness while dancing might make them feel more connected.
Another way is to join Harry Potter fan groups on social media platforms like Facebook or Reddit. Ask the members if they know of any good 'Harry and Ginny jealous fanfiction'. Chances are, they'll be able to point you in the right direction. There are often discussions about different fanfictions in these groups.