The idea of sacrifice also pops up a lot. Given the nature of the Fate series, the characters may be in situations where they have to sacrifice for one another. In fanfics, this can be explored in different ways, like Saber sacrificing her power to protect Rin and Shirou.
Another common theme is the growth of their individual characters through their interactions. For instance, Shirou may learn more about his ideals from Saber and Rin, and they in turn might change their views on things like the Grail War and their own destinies as they get closer to him. This growth can be both in terms of power and in terms of emotional maturity.
One common theme is the growth of their relationship. Starting from their initial interactions which might be a bit rocky, they gradually come to understand and care for each other more deeply. Another theme is their shared journey in the magical world. They face various challenges together, and this strengthens their bond.
One common theme is the exploration of their different personalities. Saber is often stoic and noble, while Rin is more headstrong and confident. Fanfics usually play around with how these personalities interact and complement each other. Another theme is the power dynamic. Given their different magical abilities, it's interesting to see how they work together or sometimes compete in the stories.
One popular 'Saber x Rin x Shirou' fanfic is 'The Three's Bond'. It beautifully weaves their relationships together in an alternate universe setting. The story shows how they support each other through various challenges.
Another theme is the struggle against fate. In many fanfics, Saber Alter and Shirou find themselves having to fight against the pre - determined path set by the original 'Fate' storyline. They try to create their own future together, which makes for an exciting and engaging read.
One common theme is friendship. Despite their different origins and personalities, Rin and Saber often develop a deep friendship in these fanfics. They learn to rely on each other and support one another through difficult times.
Often, these fanfics highlight the contrast between Rin's modern - day mage nature and Saber's chivalrous, medieval - like essence. They play on the idea of two very different characters coming together.
Another theme could be redemption. Maybe Shirou as a Dead Apostle is seeking redemption through his relationship with Saber. And Saber might be trying to save him from his dark path. It's also common to see themes of forbidden love, as their natures seem so different that their relationship might be seen as something not allowed in the normal Fate world order.
The theme of sacrifice also often appears. Shirou is known for his self - sacrificing nature, and in fanfics, this can be explored further in relation to Saber. For instance, how his willingness to sacrifice himself affects Saber and how she might respond to it, either trying to prevent it or being inspired by it.
Love is a very common theme. Their relationship, which was complex in the original work, is often explored more deeply in fanfiction, showing different aspects of their love for each other.
One common theme is the exploration of their growing relationship. It could be about how they fall in love, from initial distrust to deep affection. Another theme is their cooperation in the Holy Grail War. They might face difficult enemies together and rely on each other's strengths. Also, self - discovery is a theme. As they interact, both Shirou and Rin may learn more about themselves, like Shirou realizing his true potential or Rin understanding her own feelings better.