To write a great Undertale Underfell Sans x Fell Toriel fanfiction, you need to research the Underfell universe thoroughly. Know the rules, the power dynamics, and the overall atmosphere. When it comes to their relationship, start with small moments. Maybe Fell Sans brings Fell Toriel a small gift, like a flower from the dangerous parts of the Underground. This simple act can start to break the ice between them. As for the writing style, use vivid descriptions to bring the Underfell setting to life. Describe the dark corridors and the menacing monsters in the background as their relationship unfolds.
A good fanfiction in this case would involve character development. Show how Fell Sans and Fell Toriel change as they interact. Fell Sans could become more empathetic towards Fell Toriel's leadership and the responsibilities she bears. Fell Toriel could learn to appreciate Fell Sans' unique skills and his ability to think outside the box. Also, don't be afraid to add some conflict. Maybe there are other monsters in the Underfell who oppose their growing relationship. This conflict can add depth and drama to the story, making it more engaging for the readers.
One idea could be a story where Fell Sans and Fell Toriel form an unlikely alliance. Maybe they start by just having chance encounters in the Underground, and over time, they realize they share a common goal, like trying to bring some sense of order to the chaotic Underfell world. This could involve them working together to deal with unruly monsters and gradually growing to respect each other.
Frisk would be a likely candidate. Since Frisk is the main character in Undertale and has a very adaptable personality. They could approach Underfell Sans with an open mind and try to understand him.
There's also 'Sibling Rivalry Reimagined' which delves deep into how their personalities from their respective universes interact. It has some really interesting character development for both Sanses. It shows how their differences can lead to both conflict and unexpected understanding. The author does a great job of portraying their emotions and the way they communicate, which is quite different from the original game's interactions.
There's 'Sans - Bound'. This fanfiction focuses on the challenges they face when they are forced to work together. It's not just about their relationship but also about the world - building in the undertale and underfell universes. The descriptions of the settings are vivid and add to the overall charm of the story.
The fan base loves these characters so much that seeing them interact in new and unexpected ways is always a treat. The relationship between them can be explored in so many different ways, from friendship to rivalry. And the unique art styles and interpretations that often come with these fanfictions add to the overall appeal. There are also some really emotional stories that can be told about them finding common ground or learning from each other, which really tugs at the heartstrings of the readers.
The comic might feature interactions and adventures between Sans and Toriel in the Undertale universe. Maybe there are some funny moments or serious storylines.
In such a fanfiction, there could be a lot of conflict. Underfell Sans is from a more hostile AU than Undertale. He might initially be distrustful when meeting the characters from Undertale. For example, he could misunderstand their kindness as weakness or a trick.
First, understand the personalities of both Toriel and your OC human well. Toriel is motherly and kind, so your OC's reactions to her should be appropriate. For example, if your OC is a tough - guy type, their initial resistance to Toriel's mothering could create an interesting dynamic.
First, understand the character of Underfell Sans. He's different from the normal Sans, more edgy and with a darker personality. Then, create an interesting scenario for the reader to interact with him. For example, a dangerous mission in the Underfell world.
Start by making a list of their distinct characteristics. Underfell Sans has a more angular appearance and a darker color palette, which can be reflected in his personality as being more cynical. Sans, on the other hand, is more approachable in appearance and personality. When writing their interactions, use these traits. Let their body language speak volumes. Underfell Sans might cross his arms and glare, while Sans slouches and gives a lazy grin. As the story progresses, these characteristics can be tweaked based on the events they experience. If they face a great loss together, it could make Underfell Sans more vulnerable and Sans more serious.