One challenge could be cultural differences. Naruto comes from a world of ninjas with its own set of traditions and values, while Soifon is from Soul Society which has a very different way of life. For example, the way they celebrate festivals or handle family matters might be completely different.
One possible plot could be that Naruto, during one of his travels to different worlds or dimensions, ends up in the world of Soul Society where he meets Soifon. They initially clash due to their different personalities and combat styles. Naruto's positive and friendly nature gradually chips away at Soifon's cold exterior. As they go on adventures together, they start to understand and respect each other more, and eventually fall in love and decide to get married. Their wedding could be a grand event with Naruto's friends from his world and Soifon's comrades from Soul Society coming together to celebrate.
Well, one possible plot could be that they start off with a rocky relationship due to their different personalities. Ichigo, being more easy - going, and Soifon, being strict. But as they are forced to work together on some mission, they gradually understand each other better. Eventually, they realize their feelings for each other and get married. Their married life could involve Soifon trying to train Ichigo to be more disciplined in his powers, while Ichigo teaches her to relax a bit more.
Ichigo, the orange - haired protagonist with his powerful zanpakuto. He has a kind heart and is always ready to fight for what's right. And Soifon, the captain of the Second Division in the Soul Society. She is known for her stealth and combat skills. In the context of this fanfiction, they are the main characters whose relationship is explored, from their first encounters to their decision to get married.
I'm not sure specifically about 'lemon' fanfiction involving Soifon and Yoruichi as it often involves inappropriate content. However, there are many great non - 'lemon' fanfictions about them that focus on their friendship, rivalry, and their roles in the Bleach universe. You can try looking on fanfiction - dedicated websites like FanFiction.net or Archive of Our Own and filter for appropriate stories.
One common theme could be the relationship dynamic between the two characters during pregnancy. It might explore how they support each other or deal with the challenges.
A life - or - death situation might prompt the kiss. For instance, if Ichigo is about to die, Soifon, having some special power in her kiss, decides to use it to save him. It could be a last - ditch effort that involves a kiss, which then has unforeseen consequences on their relationship.
It could be a completely original goddess created by the fanfiction writer. This goddess might have unique powers like the ability to control the elements in a way different from the ninja in Naruto's world. She could be the goddess of light, for example, with the power to banish darkness and heal the sick.
If it's a crossover with Attack on Titan, Naruto might be married to Mikasa. Given Mikasa's strong and protective nature and Naruto's never - give - up attitude, they could be a formidable pair. They would face the Titans together, with Naruto using his ninjutsu and Mikasa her combat skills.
One possible plot could be that they are forced into a situation where they have to kiss as part of a mission or a spell gone wrong. For example, a powerful enemy casts a spell that binds them together and the only way to break it is through a true love's kiss. At first, they are both hesitant and angry about it, but as they get closer, they start to feel a strange connection.