Mikey might be a character created to tell a story about Pop Rocks. He could be a fictional child used to illustrate the appeal or novelty of these candies. For example, he could be a curious and adventurous little boy who wasn't afraid to try new things, like Pop Rocks, which were quite different from other candies at the time.
It depends on how you define 'real'. Some aspects might be based on real-life experiences, but it could also have fictional elements for entertainment purposes.
In many fanfictions, Mikey is the optimist. He looks at the world with a positive outlook and tries to find the good in Rahzar. His friendly nature makes it easier for him to approach Rahzar, even though Rahzar might seem intimidating at first. Rahzar is usually depicted as having a lot of strength and power. He's a force to be reckoned with, but his character can also be complex, with hidden emotions that Mikey helps him uncover.
April and Casey might also be part of this fanfiction. April could use her reporting skills to try and figure out what's going on with Mikey's mutation, and Casey would be ready to fight any new threats that come along because of Mikey's changed state. Also, Splinter, as their sensei, would be guiding them all through this difficult time, providing wisdom and training to help Mikey control his new powers if he has any.
The main characters include Little Nicky, who is the protagonist. He's the son of Satan. Satan is a key character as he's in charge of Hell and sends Nicky on his mission. Nicky's two brothers are also main characters as their actions drive the plot. They are evil and their escape to Earth and the chaos they create is what the whole story revolves around. Additionally, there could be some side characters like the people Nicky befriends on Earth. They help him in his journey to some extent, for instance, by teaching him about human ways and giving him support when he's trying to face his brothers.
The story of Little Nicky is about the son of Satan. Nicky is sent to Earth on a mission. He's not as evil as his other brothers and has a rather clumsy and naive nature. He tries to stop his evil brothers from causing chaos on Earth. He meets various characters during his adventure and has to learn to fit into the human world while also trying to fulfill his task.
Yes, there are quite a few out there. You can start by looking on fanfiction websites like Archive of Our Own. Just search for 'Alex and Nicky OITNB' and you'll find a variety of stories written by different fans. Some might focus on their friendship, while others could explore different scenarios within the OITNB universe.
Character development is a key element. Writers often explore Nicky's personality more deeply, showing her growth and how she adapts to the dangerous world Bourne inhabits.