Definitely their colleagues from the precinct. Characters like Charles, Terry, and Rosa can add a lot of humor and different dynamics to the story. Charles could be the over - enthusiastic friend who always has some wild ideas. Terry could be the voice of reason and the one who gives them tough love when needed. Rosa can bring in her no - nonsense attitude and be a great source of unexpected help.
Another great character to include could be an old friend from their past. Maybe someone from Jake's childhood who resurfaces and causes a bit of jealousy in Amy. Or an old college friend of Amy's who comes to visit and challenges the relationship in some way. These types of characters can introduce new conflicts and also help in exploring the deeper aspects of Amy and Jake's relationship.
In fanfic, Amy Cahill might be seen as a leader - type character. She is likely to be the one who comes up with plans and strategies. Jake Rosenbloom could be her sidekick or partner in crime. He might have a more laid - back personality compared to Amy, but when it comes to important things, he is just as reliable. For example, he could be the one who calms Amy down when she gets too stressed during their adventures.
Caleb could be a great character to include. He could offer his practical help, like building things for the baby or helping out with the farm work so that Amy and Ty can focus on the pregnancy. Lou could also be important as she might be full of advice, being an older sister. And of course, Jack, who could give his wisdom and share his own experiences of raising a family.
Dan could be a great addition. His quick thinking and adventurous spirit could add more action to the story. He could also be a source of conflict between Ian and Amy as he might not trust Ian at first.
Princess Bubblegum would be a great addition. She could offer her scientific knowledge to help Cake and Jake in their adventures. For example, if they encounter a strange chemical reaction or a mechanical problem, she could come up with a solution. Finn is also a good choice. His bravery and sword - fighting skills would be useful when they face dangerous situations. And Marceline the Vampire Queen could add an element of mystery and her vampire powers might come in handy at times.
The main characters are Jake and Amy, and of course, their new baby. Jake is probably a fun - loving and somewhat childish character, while Amy is more serious and career - driven. Their baby is the new center of their world in this fanfiction.
One common theme is friendship - turned - love. Amy and Jake often start as friends and then gradually develop deeper feelings for each other.
Sonic himself is a must - include. His speed and adventurous spirit drive the story forward. Tails is also great as he can provide technical support and is Sonic's loyal friend. And Dr. Eggman, as the main antagonist, always adds conflict and excitement to the story.
Vegeta is a great choice. His rivalry with Goku adds a lot of drama and action to a fanfic. Also, Piccolo, as he has a long history with Goku and has been both an enemy and a friend. Another good character could be Gohan, Goku's son, as it can explore their father - son relationship further in the fanfic.
Another good character to include is Lex Luthor. He could be the mastermind behind a plot to drive a wedge between Batman and Wonder Woman. His devious mind and resources would make him a formidable antagonist, and his interactions with the two heroes would add a lot of drama to the story.
Optimus Prime is a great choice. His leadership and wisdom can add depth to the story, and his relationship with Bumblebee can be explored further. Also, Sam Witwicky, as he has a strong bond with Bumblebee in the movies. Their friendship can be a central part of the fanfic.