Some fanfictions introduce new antagonists. For example, a jealous mermaid from Ariel's pod who feels that Ariel has abandoned them for Eric. She could try to sabotage their relationship by causing misunderstandings between them.
Often, in fanfiction, Ursula can still be a main antagonist. She might come back with a new plan to break up Ariel and Eric, maybe using a different form of magic or disguise this time.
Perhaps in the fanfiction, Ariel and Eric get married and have to deal with the cultural differences between the underwater world and the human world. For example, Ariel has to learn the proper etiquette in Eric's kingdom while Eric tries to understand the unique traditions of Ariel's mermaid family.
Perhaps in a fanfiction, Ariel and Eric will have a family of their own. They will raise their children to understand both the land and the sea, creating a unique bond between the two worlds.
One possible fanfiction could be that Ariel and Eric discover a hidden underwater kingdom that was lost long ago. They embark on a journey to learn about its history and find that it holds the key to a magical power that can save both the underwater and land worlds from a new threat.
In the fanfiction, a romantic plot could involve Ariel getting the ability to walk on land permanently. Eric then takes her on a tour of his kingdom, showing her all the beautiful places. At sunset, he takes her to a cliff overlooking the ocean and proposes to her, making it a very romantic scene.
One interesting storyline could be Ariel and Eric exploring new lands together that are beyond the sea and the shore they know. They could discover hidden islands with magical creatures and have adventures while learning more about each other's worlds.
One possibility is that they immediately start planning their future. Since they come from two different worlds, they'd have to figure out how to make their relationship work. Maybe they start building a place where both of them can be comfortable, half on land and half in the sea. And they could start spreading the message of love and unity between humans and mer - people.
The main characters are Ariel, a mermaid who dreams of the human world; Prince Eric, the human that Ariel falls in love with; and Ursula, the evil sea witch who makes a deal with Ariel.
In the original 'Ariel Little Mermaid' story, the most prominent character is the little mermaid. She has a strong will and a deep longing for the human world. The prince, a handsome but perhaps a bit oblivious young man, is an important character as well since he is the focus of the mermaid's love. Her sisters also feature prominently. They are all mermaids like her and they have a sisterly bond. They are worried about her when she makes her dangerous deal to become human and are part of the story's emotional fabric.
The main characters are Ariel, the little mermaid herself, the prince she falls in love with, and the sea witch.
The actress playing Ariel in the Little Mermaid story is Halle Bailey. She has been praised for her portrayal and has given the character a unique charm.