Their relationship could become stronger. The shared experience of expecting a baby might bring them closer together as they support each other through the various stages of pregnancy, like doctor appointments and morning sickness.
They could be original characters created specifically for this fanfiction, where they are two individuals with their own personalities, dreams, and flaws, and the kiss is a significant moment in their relationship development.
Perhaps they discover that Frida is pregnant during a time of great chaos in their lives. They then have to balance their normal daily activities with the new reality of impending parenthood. For example, Manny might be in the middle of an important work project while Frida is dealing with morning sickness.
One possible plot could be that Manny and Frida are friends who have always had a bit of an unspoken attraction. One day, during a moment of shared celebration, like after achieving a common goal, they share a spontaneous kiss that surprises both of them and then they have to figure out what this new development means for their relationship.
The main characters are clearly Manny and Frida. Manny is often depicted as a brave and somewhat impulsive character. Frida, on the other hand, is strong - willed and intelligent. Their relationship is central to this fanfiction, especially with the aspect of them kissing.
Maybe it could be about Manny and Frida finally realizing their feelings for each other and sharing a kiss during a dangerous adventure. For example, they are facing a powerful enemy and in a moment of relief after overcoming a big obstacle, they kiss.
One great Manny x Frida fanfic could be 'The Adventure of Manny and Frida' which might focus on their journey together in a fictional world. It could show how they overcome obstacles and grow closer.
When writing a Manny x Frida fanfic, it's important to create a believable world for them. If it's set in their normal environment, describe the setting in detail. If it's a different world, make sure the rules of that world are clear. Also, don't be afraid to add some conflict, like an outside force trying to break them apart, to make the story more engaging.
I'm not sure specifically if there is a fanfiction with that exact plot. You could try searching on major fanfiction websites like Archive of Our Own or FanFiction.net.