Perhaps the fanfiction could have a plot where an external threat forces Kallen, Lelouch, and Shirley to work together closely. Kallen has to put aside her feelings for Lelouch as she sees how much he loves Shirley. During their cooperation, Kallen discovers new aspects of herself and forms a deep friendship with Shirley. Lelouch, in turn, realizes how much Kallen has grown and they all end up in a more harmonious relationship, not in a romantic way for Kallen and Lelouch anymore, but as friends who respect and support each other.
One possible plot development could be that Kallen starts to question her own identity and purpose without Lelouch in a romantic sense. She might then throw herself into her work or other relationships. Meanwhile, Shirley and Lelouch could face challenges in their marriage, like political or social pressures, and Kallen might be reluctantly drawn back into their lives to help them.
In such a fanfiction, Kallen might initially be heartbroken. She has deep feelings for Lelouch. But she could also be very stoic about it, choosing to focus on the greater cause they were all fighting for. Maybe she distances herself from Lelouch and Shirley to avoid any awkwardness or painful reminders.
Well, in this fanfiction plot, perhaps they get married as a strategic move at first. Lelouch thinks it will strengthen his position among the resistance forces with Kallen by his side as his wife. But as time goes on, they start to develop real feelings for each other. Kallen, who was initially skeptical, begins to see Lelouch in a new light and they build a relationship based on mutual understanding and respect. The story could then focus on how they navigate their new married life while still dealing with the political and military challenges around them.
One possible plot could be that after a dangerous battle where they almost lost each other, the tension and relief lead to a kiss. It could be a moment of realization for both of them about their deeper feelings.
One challenge could be political opposition. Since they come from different backgrounds, there may be groups who oppose their union for political reasons. Another is the public perception. They might have to deal with the opinions of the general public, which could be divided.
Another theme is unity. Kallen and Lelouch come from different backgrounds. Their marriage symbolizes the unity of different factions or ideologies. In the fanfictions, this often leads to a more harmonious world where different groups start to cooperate more. For instance, it might show how their union affects the relationship between the Britannians and the Elevens.
One possible fanfiction could be a post - war scenario. After the chaos and destruction in the Code Geass world, Lelouch and Kallen, having fought side by side, realize their deep connection. They start to rebuild the world together and gradually their friendship turns into love. Eventually, they get married in a small, private ceremony attended by their closest friends and allies. The fanfiction could focus on how they overcome the differences in their backgrounds and the challenges of leading a new world while being in love.
One possible plot could be their adjustment to married life while still dealing with the political aftermath in their world. They might face challenges from different factions who are not happy with their union.
I also like the fanfiction 'Beyond the War: Kallen and Lelouch's Married Life'. It delves into their married life, showing how they support each other in building a new world. It shows their daily interactions, the little arguments and the great love they have for each other.
Well, at first, it might be a bit rocky as they get used to living together. But as time passes, they start to understand each other better. For example, Lelouch might learn to be more open with Kallen about his plans, and Kallen could teach Lelouch to relax more.
In lemon fanfictions about Lelouch and Kallen, their relationship often takes on new and interesting dynamics. Sometimes, it might explore their unspoken feelings in the context of the story's unique plot twists. It could be a way to delve deeper into their characters, beyond what the original anime might have shown.