The theme of redemption can be found in many 'sesshomaru x kagome mate fanfiction'. Sesshomaru may have a dark past or actions that he needs to atone for, and Kagome's love and influence help him on that path. Another theme is the exploration of new powers. Their union may unlock new abilities for either or both of them. And of course, the theme of acceptance, as they have to accept each other completely, flaws and all, in order to have a successful relationship.
Love against all odds is also a frequent theme. Given their initial enmity or indifference towards each other, seeing them fall in love and become mates is a central aspect. Their relationship often has to overcome obstacles like other suitors, family expectations (in sesshomaru's case, perhaps his clan's view), and their own personal biases.
One common theme is the overcoming of differences. Sesshomaru is a demon and Kagome is a human, so there's often a story about how they bridge that gap. Another theme can be the protection aspect, with Sesshomaru protecting Kagome from various threats.
Common themes include the power dynamic between them. Sesshomaru is a powerful demon and Kagome has her own spiritual powers, so how they interact in terms of power is often explored. Friendship is also a theme that can develop into something more. As they face various challenges in the Inuyasha universe, they start to rely on each other, which can lead to deeper emotional connections. And sometimes, there's a theme of redemption for Sesshomaru, with Kagome being a part of that journey.
One common theme is the growth of their relationship. Starting from distrust or indifference, they gradually come to understand and care for each other. Another theme could be adventure. They might go on quests together, facing various demons and challenges, which brings them closer. Also, the theme of cultural clash might be present, as kagome is from a different time and has different values compared to sesshomaru.
One common theme is the idea of 'opposites attract'. Sesshomaru is often portrayed as cold and aloof, while Kagome is warm and empathetic. Their different personalities coming together is a popular concept.
One common theme is the struggle to adapt. For example, Sesshomaru has to deal with Kagome's human emotions and limitations in her body, while Kagome has to handle Sesshomaru's demon powers. Another theme is the confusion it causes among other characters. They might mistake the swapped Sesshomaru and Kagome for having changed in some other way.
One common theme is the idea of forbidden love. Since Kagome is a human and Sesshomaru is a demon, their relationship goes against the norms of their respective worlds. Another theme could be redemption. Sesshomaru may find redemption through his relationship with Kagome, becoming more in touch with his emotions. Also, the theme of self - discovery is often present. Kagome may discover new aspects of herself as she falls for Sesshomaru, and vice versa.
One idea could be that their relationship starts as an unexpected alliance against a common enemy. As they spend more time together, they gradually develop feelings. When Kagome discovers she's pregnant, it could bring a new level of complexity to their relationship. Sesshomaru, being a proud demon, might initially struggle with the idea of impending fatherhood but then grow into a protective and loving partner.
One common theme is the forbidden love aspect. Since Kagome is often paired with Inuyasha in the original series, a relationship with Sesshomaru goes against the expected. Another theme is power dynamics, as Sesshomaru is a very powerful demon and Kagome has her own unique powers.
One common theme is possessiveness. Since Sesshomaru is yandere in these fanfics, his extreme possessiveness over Kagome is often a central element. He doesn't want to share her with anyone and will go to great lengths to keep her by his side.