Leo's personality would change in a way that he'd become more selfless. His focus would shift from mainly his ninja duties to also taking care of this new life. He'd sacrifice his own comfort and free time to ensure the baby's well - being. He might also become more empathetic towards others who are in vulnerable situations, seeing things from a new perspective as a caregiver.
He'd probably become more nurturing. Leo is already a leader, but having a baby would bring out his softer side. He'd be more patient and understanding, not just with the baby but also with his brothers. For example, if his brothers made a mistake while helping with the baby, he'd be more forgiving instead of being overly critical like he might have been before.
Their relationship would likely become more centered around the baby. They would have to work together as a team to take care of it. There would be less time for just the two of them, but in a way, it would bring them closer as they share this new responsibility.
Well, one possible plot could be that Leo discovers an abandoned baby during one of his patrols. He decides to take the baby under his wing and protect it. His brothers are initially skeptical but soon come around. They then have to figure out how to take care of the baby's basic needs like feeding and clothing while also keeping it safe from the various threats in their world.
It could become more complex as they start to think about the future. They would have to consider how to raise the child within the context of their different backgrounds. Leo, being a turtle and a part of the TMNT family, and Karai, with her own history. This might lead to some disagreements but also deeper conversations about their values and what they want for their family.
Their relationship would likely become more committed. With a baby on the way, they would have to rely on each other more. Leo might become more protective of Karai during her pregnancy, and Karai would start to see Leo in a new light as the father - to - be. After the baby is born, they would be united in their love and care for the child, which would strengthen their bond.
After the kiss, their relationship could become more complicated. Leo might start to feel conflicted between his duties as a ninja turtle and his feelings for April. April, on the other hand, could become more protective of Leo. They might start to have secret meetings to avoid the prying eyes of Leo's brothers and other people in their lives.
The other Turtles might be shocked at first. Donnie would probably start analyzing the situation, trying to figure out if it was a smart move or not. Mikey might make some jokes about it, while Raph would be more skeptical and might even be a bit angry, thinking Leo is making a mistake.
You can make it unique by adding a different time period setting. For example, set it in a future where technology has advanced and there are new ways to deal with a male turtle's pregnancy.
At first, their relationship might be filled with tension. Leo is a hero with strong moral values, and Karai has a more ambiguous past. But as they spend more time together, they start to understand each other better. Their relationship could develop into a deep and loving one as they support each other through various challenges.
Yes, there are likely some fanfictions out there about Leo and Karai kissing in the 2012 TMNT universe. You can try searching on popular fanfiction websites like FanFiction.net or Archive of Our Own.
One common theme is leadership. Since Leo is often seen as the leader, in female Leo fanfiction, it explores how she takes on that role in different ways. Another theme is family. It shows how she interacts with her brothers and how the family dynamic is affected by her being female. Also, self - discovery is a theme, as she figures out her place in the TMNT world.