Growth is also a common theme. Frisk may grow in confidence and strength under Undyne's influence, while Undyne might become more understanding and less hot - headed because of Frisk. And of course, there's the theme of adventure. Since they are in the Underground world which is full of mysteries, many fanfictions have them going on adventures together, facing monsters and solving puzzles.
Common themes include redemption and acceptance. Undyne may have to accept Frisk's non - violent ways, and Frisk may help Undyne see a different side of things, which is a form of redemption for her more violent tendencies. Additionally, loyalty is often explored. As their relationship develops, they show loyalty to each other in the face of various threats and challenges in the Underground.
One common theme is friendship. Since the reader is often involved, it shows how they build a friendship with Undyne, like learning to understand her warrior - like nature.
One common theme is the fish - out - of - water situation. Since Undyne is from her own game world, when she is placed in another universe in a crossover, she has to adapt. For example, in crossovers with modern - day Earth settings, she has to understand new technologies and social norms. Another theme is power comparison. When she meets powerful characters from other franchises, like in a crossover with the Avengers, there's a comparison of her strength with the likes of Thor or Hulk.
One common theme could be the challenges of pregnancy. Since Undyne is a strong character, it might be interesting to see how she copes with the physical and emotional changes that come with pregnancy. Another theme could be the relationship between Undyne and her partner during this time, like how they support each other.
The theme of growth is often seen. Both characters grow as individuals within the relationship. Alphys may become more outgoing and Undyne may become more empathetic. Also, the theme of adventure in their relationship is present in some fanfictions, where they go on adventures together in the Underground, strengthening their bond along the way.
Adventure is a major theme. Female Frisk embarks on all sorts of exciting journeys in the Underground. It could be exploring new regions or solving complex puzzles. Also, the theme of redemption can be found. Sometimes she helps the monsters in the Underground find redemption or she herself experiences it in some way. For instance, if she made a mistake in the past, she tries to make up for it.
Themes like good versus evil are quite common. Even though the two stories have different manifestations of good and evil, in 'Harry is Frisk' fanfiction, they are often blended. For instance, Harry might face the same kind of moral dilemmas as Frisk when dealing with the antagonists in Frisk's world. And there's also the theme of growing up and maturing, as both characters have their own arcs related to that in their original stories, and in the fanfiction, it can be further explored.
Another one is 'Frisk and Undyne's Adventure'. This story focuses on their adventures outside of the typical Underground scenarios. They go on a journey together and discover new things about each other and the world around them. It has a lot of fun and light - hearted moments as well as some deeper, more meaningful exchanges between the two characters.
Another theme could be adventure - related. Since they are both characters from the game Undertale which has an adventure - based storyline. They might go on adventures together in the fanfiction, facing challenges and growing closer as a result. Maybe they team up to save the Underground from a new threat or something similar.
One common theme is friendship. Papyrus and Undyne are often shown building a strong bond of friendship through various adventures or just daily interactions in the Underground. Another theme is mutual respect. They both recognize each other's strengths, like Papyrus admires Undyne's fighting skills and Undyne respects Papyrus's determination.