The theme of self - doubt can be seen often. Tails might doubt his abilities compared to Sonic, and Sonic might doubt his leadership at times. These moments of self - doubt can lead to crying as they struggle with their insecurities. It makes their relationship more interesting as they have to support each other through these emotional lows.
Betrayal is also a common theme. If someone they trust betrays them, Sonic and Tails would be deeply hurt and likely to cry. This shows their vulnerability. Also, the theme of feeling powerless. When faced with a force too strong for them to handle, like a powerful new enemy, they might cry in frustration and fear. It adds depth to their characters as they are not always the invincible heroes.
One common theme is loneliness. Tails often being a sidekick might feel left out or alone at times, and this can lead to him crying. Another theme could be failure. When he fails at a mission or invention, he might break down in tears. Also, the loss of a friend or a loved one is a common theme. If Sonic or any of his other friends were in danger or lost, Tails would be deeply affected and cry.
Guilt is a possible emotional theme. For example, if Tails makes a mistake that he thinks endangers Sonic or the world, he would feel guilty and cry. Betrayal could be another theme. If someone he trusts turns against him, his crying would be a natural reaction. Also, the theme of inadequacy. If Tails feels he's not good enough to help Sonic in a crucial moment, that could bring him to tears.
One common theme is loyalty. They are always there for each other no matter what. For example, in many fanfictions, Sonic will risk his life to save Tails, and Tails will use his intelligence to get Sonic out of tricky situations. Another theme is growth. They both grow as characters, Sonic might become more patient and Tails more confident as they face different challenges together.
Friendship is a very common theme. For example, in many fanfictions, Tails forms a strong bond with female characters like Amy or Cream while they go on adventures together. Another theme is cooperation. They often have to work together to overcome a common enemy or solve a problem, like in stories where Tails and Blaze team up.
Often, there is a theme of power and its control. The Werehog form gives Tails new powers, and in many fanfictions, he has to learn how to master them without causing harm. For example, in some stories, he might accidentally cause destruction while still getting used to his enhanced strength. It's also about his journey to use these powers for the right reasons.
Innovation in pranks can also be a theme. Writers often come up with really creative and unique pranks that Sonic plays on Tails. It could be something related to Sonic's super speed or Tails' inventions, making the pranks something that could only happen in the Sonic universe.
A common theme is friendship. Just like in the Sonic franchise in general, the relationship between Sonic and Female Tails is often explored in terms of their loyalty and support for each other. They might go on adventures together, relying on each other's unique skills.
Isolation is also a theme. Sometimes they get separated from their friends or find themselves alone in a scary place. This heightens the sense of fear as they have to rely only on themselves and each other. They have to deal with the situation without the full support of their usual group, which makes the story more intense.
Well, a prevalent theme is redemption. Tails may try to redeem Sonic from the dark influence of Sonic EXE. Also, the theme of mystery is common. The origin of Sonic EXE and how Tails can stop it are often shrouded in mystery in these fanfictions. Additionally, survival is a theme as Tails has to survive the attacks and threats from Sonic EXE while trying to find a solution.
Another theme could be Tails' growth. In some fanfictions, his overprotective nature might be a sign of his maturing. He realizes the dangers that Sonic faces and tries to be more proactive in protecting him. This can also lead to Tails developing new skills or strategies in the stories. For example, he might study more about Sonic's enemies to better protect him. And this growth theme can be intertwined with the overall plot of the Sonic universe in the fanfiction.