One interesting female Cuphead fanfiction could be about a female character in the Cuphead universe who has special powers to heal the other characters. For example, she might be a fairy - like being that uses magic to restore the health of Cuphead and Mugman when they are in tough battles against the devilish bosses. This would add a new dynamic to the existing story.
One idea could be exploring Cuphead and Mugman's childhood. Maybe they had a special adventure before the events of the game. Another idea is to create a fanfiction where they meet new characters in a different part of the Inkwell Isles that has a unique theme, like an underwater world. A third idea could be a story where Cuphead has to face his fears without Mugman by his side for a change.
One interesting Cuphead love story could be between Cuphead and a kind-hearted flower in the Inkwell Isles. Cuphead, during his adventures, stumbles upon a flower that has the ability to heal his wounds. Over time, Cuphead starts to feel a special connection with the flower as it always seems to be there for him when he's in a tough spot.
One idea could be a Cuphead crossover with Super Mario. Cuphead and Mugman could find themselves in the Mushroom Kingdom, facing off against Bowser's minions alongside Mario and Luigi. They could use their unique shooting skills to help in battles.
Another interesting concept is an OC that is a traveling musician in Inkwell Isles. This OC could meet Cuphead and Mugman during their travels and join them on their quests. They could use their music to soothe enemies or even as a form of attack, like creating sonic waves that stun bosses. It would add a unique element to the existing Cuphead world.
One idea could be that the characters from Cuphead end up in the world of Batim. Cuphead and Mugman might be mistaken for new ink creations in the studio. They could then have to deal with the strange and often menacing creatures in the Batim world while trying to find a way back to their own.
A really engaging storyline could be where baby Cuphead and Mugman are transported to a different dimension. In this new place, everything is upside down and the rules are different. They have to figure out how to get back home while also dealing with the strange inhabitants of this dimension. It could be filled with action - like running from giant bugs or making friends with a friendly but odd - looking alien - like creature.
Power and temptation are also popular themes. Since she is a devil, fanfiction might delve into how she uses her power to tempt the characters or how they resist her. There could also be themes of redemption, where the female devil has a change of heart, although this is less common given her nature.
One popular baby Cuphead fanfiction might be those that explore his early days in the Inkwell Isles. For example, stories where he first discovers the magic of the world around him. Maybe he meets some of the friendly characters like Elder Kettle when he was just a little baby Cuphead and they have simple adventures, like learning to make the special potions Elder Kettle is known for in a very cute and innocent way.
One popular Cuphead reader fanfiction might be those that focus on Cuphead's adventures in different lands within the game's universe. For example, a story could be about Cuphead exploring a new, uncharted area filled with strange enemies and even stranger allies. Another could be centered around the relationship between Cuphead and Mugman from a reader's perspective, showing their brotherly bond in new and interesting ways.
One plot idea could be that Cuphead and Baroness have to team up against a greater evil in the Cuphead world. Maybe a new powerful devil - like character shows up and they realize they need each other's skills to defeat it.