Swap Cop Sans x Criminal Underfell Sans Fanfiction: How Do the Characters' Personalities Differ in This Concept?

Often, there's a plot twist where the Criminal Underfell Sans reveals a hidden side of himself that is not entirely bad. He might have been forced into a life of crime due to certain circumstances. And this revelation makes the Swap Cop Sans see him in a new light. This could lead to a change in the power dynamic between them and also the direction of the story as a whole.

Another theme is friendship or partnership. They often come together to face challenges in the Underground. For example, in many fanfictions, they join forces to defeat a powerful monster or solve a mystery that threatens their world. This theme of unity despite their differences is really appealing.

The contrast between the two characters. Underswap Sans is more laid - back and friendly compared to Underfell Sans who is more rough and edgy. When they interact in fanfictions, it creates a lot of interesting dynamics, like how they might clash or gradually understand 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.

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.

A plot could revolve around an accident that causes their universes to merge partially. Underfell Sans and Sans find themselves in a strange new reality where they have to figure out how to get back to their own universes. Along the way, they learn about the differences and similarities in their lives, and this leads to some really interesting character development.

You can start by looking on Archive of Our Own (AO3). It has a large collection of fanfictions for various fandoms, including the Undertale AU crossovers like Underswap Sans x Underfell Sans. Another place could be Fanfiction.net, though the quality may vary more there. Additionally, Tumblr sometimes has users sharing or recommending such fanfictions in the Undertale fandom tags.

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.

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.

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.