Romantic confessions are also a common theme. When a character is about to confess their love to someone, they usually have 'butterflies in their stomach'. It's a moment full of tension and emotion. Additionally, getting ready for a big performance, like on stage or in a sports event, can bring about this feeling as well. The pressure and the hope of doing well create that fluttery, nervous feeling.
There may not be a lot of pre - known fanfics that are exactly 'butterflies in my stomach' without worms. However, you could consider writing your own. Think about the emotions that 'butterflies in my stomach' represents, like nervousness or excitement in a romantic or thrilling context. Then create a story that focuses on those emotions without involving worms.
Growth and transformation can be another theme. Butterflies go through a transformation from caterpillars to their beautiful winged forms. In fanfics, this can be used as a metaphor for the ponies' own personal growth. For instance, a pony might learn a valuable lesson from observing the life cycle of a butterfly and then apply it to their own life to become a better version of themselves.
Survival is a very common theme. Given the post - apocalyptic setting of 'The 100', many fanfics explore how the characters continue to find food, water, and shelter. They also deal with the threats from other groups and the harsh environment.
Another theme is their relationships with other factions in the Warhammer 40,000 universe. They might interact with the Space Marines, the Imperial Guard or even face off against the forces of Chaos. These interactions can create interesting storylines, like a joint mission between the Sisters of Battle and the Space Marines where they have to overcome their differences to succeed.
The idea of future - planning could also be a theme. With a baby on the way, Sonic and Amy would need to think about things like where they will live, how they will raise the child, and what kind of future they want to provide for their little one. This can add a lot of depth and realism to the 'sonamy pregnant fanfic'.
Often, friendship themes can be common. Since Naruto is about a group of friends, the tickling might be used in a friendly, playful context among the characters like Naruto, Sasuke, and Sakura.
The theme of loyalty also often comes up. In Twilight, there is loyalty among the Cullens, and between Bella and her friends. In fanfics, this loyalty can be tested in various situations. Maybe a character has to choose between loyalty to their vampire family and helping a human friend in a difficult situation. These themes can be found in many Twilight fanfics even when we move away from inappropriate 'lustful thoughts'.
One common theme could be hunger and the search for food. Since the stomach growl indicates hunger, the fanfic might focus on ponies trying to find something to eat in their magical world.
Common themes in 'naruto stomach ache fanfic' might include the exploration of Naruto's vulnerability. Since he's often shown as a strong and energetic character, a stomach ache can make him seem more human. There could also be themes related to the ninja world's medical knowledge. How do they treat such a condition? Is there some special herb or jutsu that can help? And of course, the emotional aspect of Naruto's pain. How does he deal with the discomfort? Does he become grumpy or more reliant on others? These are all aspects that could be explored in such fanfics.
Spiritual and philosophical exploration is also prevalent. Concepts such as karma in Indian literature or the idea of harmony in Chinese and Japanese literature are often delved into. Social hierarchy and the struggle for status or identity within a society are also common themes that can be found in various Asian literary works.