Vernon is likely a character within the Psychonauts universe. In the context of the Vernon Ghost Story, he's probably the central figure who has some sort of encounter or relationship with the ghosts.
Vernon could be anyone. Maybe he's an old man in the neighborhood who loves to share spooky tales from his youth. Or perhaps he's a young person who had a strange encounter and turned it into a ghost story. Without more context, it's hard to say exactly who he is.
Petunia could be a great addition. Her relationship with both Harry and Vernon adds a lot of complexity. She could be the mediator or the one causing more trouble between them, depending on the plot.
In some fanfiction, Uncle Vernon develops by becoming more accepting. For instance, he may start to see Harry not just as a freak but as a person with unique abilities that can be useful. He might begin to tolerate the wizarding world a bit more, especially if he realizes that Harry can use his magic to protect the family from certain threats.
In the traditional TMNT universe, male turtles like Leo getting pregnant goes against the biological norms of the franchise. However, in fanfiction, anything can be reimagined. Some fanfiction might use magic or some out - of - the - box concepts to make such a situation possible, but it's not part of the official TMNT lore.
In this fanfiction, the TMNT might escape by first observing their captors' routines. If the Shredder has minions guarding them, they could wait for a shift change or a moment of inattention. Donatello might be able to hack into any security systems if there are any. Also, they could use their knowledge of the sewers to find a way out. Maybe there's a hidden passage that the Shredder doesn't know about. And of course, their ninja skills would come in handy for sneaking past guards and making a quick getaway.