Kale could be paired with Caulifla. Since they have a pre - existing relationship in the original series, in a futanari fanfic, their bond could be explored further. Maybe they could combine their powers in new and unique ways, or have to protect each other in a dangerous situation.
Vegeta is also a good choice. His prideful nature and his own strong power would contrast well with Caulifla. They could have a rivalry that turns into an unexpected alliance in a fanfic, especially with Caulifla's futanari aspect adding an extra layer of complexity to their relationship.
Goku could be a great character to pair with Caulifla. His powerful Saiyan abilities and his experience in different battles could create interesting interactions with Caulifla in her futanari form. They could train together or face off against a common enemy.
A popular idea might be a fanfic that delves into Caulifla's relationships with other characters in her futanari form. It could explore how her new form affects her interactions, like with her friends or rivals. For example, how she might use her unique abilities in battles against foes who underestimate her due to her different form.
Yoshi would be an excellent character to pair with Bowuigi. Yoshi's friendly and helpful nature can contrast or complement Bowuigi's personalities. Donkey Kong is another good choice. His brute strength can be a great counterpoint to Bowuigi's more strategic thinking. And Toad could be added for his loyalty and sometimes comical nature.
A rogue could be a great character to pair with an artificer in fanfic. The rogue's stealth skills combined with the artificer's gadgets can lead to some really interesting heist - like scenarios. For example, the artificer could create a device that disables security systems while the rogue sneaks in to steal a valuable item.
Tanjiro would be a great character to pair with rengoku. Their different personalities could create an interesting interaction. Tanjiro's kind - hearted nature and rengoku's fiery determination could lead to some great storylines.
Hawks is a great character to pair with Dabi in fanfic. Their relationship in the original story is complex and full of tension, which can be explored further in fan - made stories. There's also Shigaraki. Since they are both important members of the League of Villains, there's a lot of potential for interesting dynamics between them in fanfics.
Naruto could be a great character to pair with Menma. Their personalities could create an interesting dynamic. Naruto's determination and Menma's more gentle nature could complement each other well in a story about friendship or even a budding romance.
Naruto himself would be a great character to pair with Raiden. Their different powers and personalities would create an interesting dynamic. Naruto's positive and determined attitude could complement Raiden's more stoic nature. Another good pairing could be with Kakashi. Kakashi's wisdom and combat experience could work well with Raiden's unique abilities. And Sakura could also be a good match. She could learn from Raiden's fighting style, and Raiden could be impressed by her medical ninjutsu skills.
I think Missandei could be an interesting character to pair with Khal Drogo in a fanfic. She is intelligent and has a strong sense of self. Her presence could bring out different sides of Khal Drogo as he interacts with someone who has a very different background from his own. Also, Ser Barristan Selmy could be paired with him. Selmy's experience and honor could clash or blend with Khal Drogo's more savage and wild nature, creating a dynamic and engaging story. And then there's Grey Worm. His stoicism and military discipline could contrast with Khal Drogo's leadership style, leading to some really interesting character - development scenarios in a fanfic.
One character that could work well with an angry Loki is Doctor Strange. Strange is used to dealing with powerful and unpredictable entities. He could either try to manipulate Loki's anger for his own purposes or try to help Loki come to terms with it. And of course, Sif. She has a history with Loki and her loyalty to Asgard could put her at odds with an angry Loki.
His sister, Charlotte Smoothie, could be a great pairing. They both have unique powers and their interactions could lead to interesting story developments, like teaming up for a mission within the Big Mom Pirates.