One common theme is the overcoming of social barriers. Since they are from different social standings in the Bridgerton world, many fanfictions focus on how they break through those barriers to be together.
Well, clearly Penelope and Colin are the main characters. Penelope is a smart and resourceful young woman, often underestimated. Colin is charming and adventurous. Their personalities create a lot of interesting dynamics in the fanfiction.
I really like 'Kate and Anthony: Unveiled Hearts'. It delves deeper into their backstories and how they might have interacted before the events of the show. The author does a wonderful job of creating a believable and engaging plot that adds new layers to their love story.
A more romantic plot could be where Colin finally realizes his true feelings for Penelope during a grand ball. He sees her in a new light, perhaps while she is dancing with someone else and he feels a pang of jealousy. Then he makes a grand gesture to win her over.
Love and courtship are very common themes. Since their relationship is at the core, many fanfictions explore how they fell in love, the courtship process, and how they overcame any obstacles in their path to be together.
One popular anthony x penelope fanfiction is 'A Love Unveiled'. It beautifully portrays their relationship development, from initial misunderstandings to deep love. The author does a great job of capturing their personalities.
One idea could be a story where Penelope and Colin travel together to an exotic location. Along the way, they face various challenges that make them rely on each other more, deepening their relationship. For example, they might get lost and have to find their way back using only their wits and each other's company.
Another way is to put them in a situation where they have to take care of someone or something together. For example, they could be in charge of a charity event. During the process, they learn about each other's leadership styles, how they handle stress, and this newfound knowledge deepens their connection. They might also see each other in a different light, which further enhances their relationship.
Some Bridgerton - themed fan communities on social media platforms like Tumblr or Reddit might also have links or even their own fanfiction written about Kate and Anthony. You can join these communities and look for posts related to fanfiction.
You can start by looking on fanfiction.net. It has a large collection of fanfics from various fandoms, including those related to Anthony and Penelope.