Well, a frequent theme is the transformation of their bond. In many of these fanfictions, we see how Rin's unwavering loyalty to Sesshomaru blossoms into love, and how Sesshomaru comes to terms with his own feelings. Also, cultural differences between the human and demon worlds often play a role. How do they bridge the gap? How do they handle the different values and traditions? These are all things that are commonly explored in such fanfictions. And of course, there's the theme of power dynamics. Sesshomaru is so much more powerful than Rin, so how does that affect their relationship, especially when they are married?
One common theme could be the exploration of their relationship's growth. It might start from Sesshomaru's initial coldness towards Rin and how it gradually thaws as they get closer. Another theme could be the acceptance within the demon world, as Sesshomaru is a powerful demon and Rin is human - or at least was human originally. And there could also be themes of family, as they build a life together and perhaps face issues related to having children or integrating into each other's 'familial' circles.
Common themes include the development of love against all odds. Given that their relationship in the original series was more of a protector - protected one, fanfictions often focus on how that changes into a romantic relationship. There may be themes related to the passage of time, as Rin has to grow up for a romantic relationship to be possible. Additionally, themes about loyalty and trust are prevalent. Since Sesshomaru has a complex personality, Rin's loyalty has to be tested and proven time and time again in these stories. And finally, the idea of building a new world or a new life together, away from the chaos of the original Inuyasha plot, is also a common theme.
One common theme could be the exploration of Sesshomaru's character development. How he, who was once a cold and aloof demon, would adapt to the idea of becoming a father. Another theme might be the changes in Rin's relationship with Sesshomaru and the others around them. For example, how would the other characters in their world react to this new development.
Yes, there are likely fanfictions out there with such a plot. Fanfiction writers often explore different relationships and scenarios that might not be part of the original canon. They can create unique stories where Rin and Sesshomaru end up getting married, imagining how their relationship could develop over time and what kind of life they would lead together.
One popular theme is growth. Fans like to write about how Rin grows from a young girl into a more confident and capable person with Sesshomaru's influence. Another theme is loyalty. Sesshomaru's loyalty to Rin and vice versa is often explored.
One common theme is growth. Rin grows up under Sesshomaru's watchful eye, and the story shows how she becomes a stronger person. Another theme is loyalty. Rin's loyalty to Sesshomaru and Sesshomaru's unspoken loyalty to protect Rin are often explored.
One common theme is growth. Rin's growth from a child to a young woman and how that affects her relationship with Sesshomaru. Another theme is protection. Sesshomaru's role in protecting Rin is often a central focus.
The theme of protection is very common. Sesshomaru is a powerful demon, and he often protects Rin from various threats in the fanfictions. Another common theme is growth, both in terms of Rin's physical and emotional growth as she spends time with Sesshomaru, and also Sesshomaru's growth in terms of his ability to care for someone else.
Protection is also a big theme. Sesshomaru feels a strong need to protect Rin, which is often explored in different ways in the fanfiction, like facing powerful enemies to keep her safe. Another theme is the exploration of an unlikely love. Their relationship defies the norms as Sesshomaru is a powerful demon and Rin is a human girl, and fanfictions like to dig into how such a relationship might work and develop over time.
One common theme is the exploration of family life. Since Sesshomaru is a demon and Rin is a human, their family dynamics can be really interesting to write about. Another theme could be the protection of their relationship from outside forces, like other demons or humans who might not approve.
Many young Rin and Sesshomaru fanfictions explore the theme of discovery. Rin discovers more about the world of demons through Sesshomaru, and Sesshomaru discovers emotions he didn't know he had because of Rin. There's also the theme of acceptance. Sesshomaru has to accept the fact that he cares for a human, Rin, and Rin has to accept the dangerous world she's in with Sesshomaru. These themes add depth to the fanfictions about them.
Protection is also a big theme. Sesshomaru is a powerful demon, and in these fanfictions, he often uses his strength to protect Rin and their baby from various threats. Love is another common theme. The love between Sesshomaru and Rin is extended to their baby, and the story might show how this love shapes the baby's life.