Obviously Chowder himself is a must - include. Mung Daal, as his mentor, also makes for great content. And Truffles, with her strict but caring nature, can add interesting dynamics to the story.
Chowder is the central character, so he has to be in there. Then, Mung Daal can bring in his wisdom and cooking expertise. Endive, with her snobbish attitude, can create some comical conflicts. Also, Schnitzel, even though he mostly says 'radda radda', can be a fun and mysterious character to include in the fanfiction.
The Warrens could be great characters to include. Their knowledge of the occult and their experience with haunted objects like Annabelle can add a lot of depth to the story. They can be the ones trying to either save Annabelle or stop her from causing more harm.
Ace is a great character to include. He was Whitebeard's adopted son, and their relationship was very deep. Stories about their interactions, whether it was Ace learning from Whitebeard or them having father - son moments, are always interesting. Marco is also a good choice. As Whitebeard's right - hand man, he could be in stories that show the inner workings of Whitebeard's crew and how they strategize and operate. Another one could be Luffy. Since Luffy had a connection with Ace and later respected Whitebeard, a fanfiction could explore their interactions.
Obviously, Bahubali himself is a must - include. His strength, courage, and leadership make him a central figure. Then there's Kattappa. His loyalty and his complex relationship with Bahubali can add a lot of depth to the story. Also, Devasena is an important character. Her love for Bahubali and her own strength as a princess can bring in elements of romance and female empowerment in the fanfiction.
The main characters are obviously Chowder and Mung. Chowder is the young, eager apprentice always looking to learn more about cooking. Mung is the more experienced one, perhaps a mentor - like figure to Chowder.
Definitely Sasuke. His complex relationship with Naruto provides a lot of material for fanfiction. You can explore their friendship, rivalry, and how they grow together. Kakashi is also a great character to include. His wisdom and unique jutsu can add depth to the story. And of course, Sakura. Her growth as a kunoichi and her relationships with Naruto and Sasuke can be interesting to write about.
Naruto himself is a must - he's the main character after all. Sasuke could also be great as his rival. Their interactions around the kit would be interesting, like if they both wanted it for different reasons. Sakura could be included too, maybe she helps Naruto figure out how to use the kit.
Well, in addition to Naruto and Urahara, Ichigo from Bleach could be a great addition. Since Urahara has a connection with Ichigo, and Naruto's energetic and positive nature could create an interesting dynamic with Ichigo's more brooding personality.
The Cullens from the Twilight series are obvious choices. They could interact with Harry in various ways. For example, Carlisle's medical knowledge and his calm, father - like presence could provide stability in a dangerous situation that Harry and Edward find themselves in.
Obviously, Adam himself is a must - include. His character has a lot of depth and potential for further development. Also, his mother would be great to include as she plays an important role in the story. And the villain from the movie could be brought back in a new and more menacing way.
Definitely Naruto himself. His determination and positive attitude can bring a lot to the story. Lala too, of course, with her fun - loving and inventive nature. Sakura could also be a great addition. She could interact with Lala in interesting ways, perhaps learning about Lala's technology and applying some of her medical skills to help Lala if she gets injured.