The interaction between them could be really interesting. Since Goku is a Saiyan used to fighting powerful foes, he would be protective of Lucy when she gets into trouble in his world. Lucy, being a student at NYU, would be resourceful and use her knowledge to help Goku in unexpected ways. For example, she could use her knowledge of physics to help Goku understand the mechanics of some of his more powerful attacks better, and in return, Goku could teach her how to defend herself using ki energy.
In the fanfic, their interaction could start with a misunderstanding. Lucy could think Goku is some kind of superhero from a cosplay event gone wrong. Goku might not understand Lucy's fast - paced NYU lifestyle. But as they spend more time together, they start to respect each other's abilities. Lucy would come to admire Goku's determination and power, and Goku would value Lucy's intelligence and her different perspective on things.
Well, perhaps in the fanfic, there is a dimension - hopping event. Lucy, who is at NYU studying some esoteric theory, accidentally opens a portal to the Dragon Ball universe. Goku senses the strange occurrence and comes to investigate. They meet and find that they can learn from each other. Lucy can teach Goku about advanced human knowledge like science and math, while Goku can show Lucy about ki and the power of self - improvement through martial arts.
Goku would interact with Kale in a way that he wants to explore her powers. He might ask her a lot of questions about how she became so strong. Kale would respond with shyness but also with pride in her abilities. They would start to train together, and Goku would encourage Kale to push her limits. As they train, their relationship would grow, and they would become friends who trust and rely on each other in battles.
Artemis could be intrigued by Goku's energy. She might see it as something similar to the divine energy she's familiar with. So she could start asking him about it. And Goku would try his best to explain about ki, using his limited knowledge of such things. They could end up sharing stories about their respective battles and adventures.
Their interaction could be really interesting. Goku is used to dealing with powerful foes and saving the world in a more action - packed way. Anne Frank is in a situation where she has to be quiet and endure. Goku could teach Anne some self - defense moves in case they are discovered, and Anne could teach Goku about patience and the importance of the written word. She might even write about Goku in her diary, and Goku would be fascinated by this strange new thing called 'writing' that can preserve memories and thoughts.
The interactions could be really interesting. Goku's straightforward and somewhat naive personality in the face of new things would contrast with the more complex relationships and personalities in Fairy Tail. For instance, when he meets Mirajane, she would probably be very kind to him, offering him food and a place to stay at the guild. Goku would then repay her kindness by helping out with any threats that come the guild's way. And with Happy, Goku would find his flying ability really cool and might even try to learn how to fly in the same way, which would be a comical scene.
Goku would probably be very friendly with Luffy. They both love to fight strong opponents and have a sense of adventure. Goku might be a bit confused by some of the wacky things in the One Piece world like the Devil Fruits at first, but he'd quickly adapt. He'd also likely be impressed by the determination of the other characters like Zoro and Sanji.
Goku's Ki - based powers and Wonder Woman's God - given abilities could create some interesting interactions. For example, Goku's Kamehameha wave, a powerful blast of energy, could potentially be enhanced or redirected by Wonder Woman's Bracelets of Submission. Her bracelets are strong enough to deflect attacks, so they might be able to shape Goku's energy blasts in new ways.
The character interactions. Naruto is a very energetic and determined character, while Lucy Nyu has her own charm. Their personalities can either clash in a fun, comical way or blend together to form a strong bond in the fanfic, which makes for an engaging read.
Goku would likely interact with Natsu in an interesting way. They both love to fight and are always looking for a strong opponent. They might start off as rivals and then become friends. Goku would also probably be friendly with Lucy, being intrigued by her celestial spirit magic.
Issei would be very likely. Since Issei is the main character in DxD, his curiosity and his own pursuit of power would make him interested in Goku. They could train together and learn from each other's abilities. Also, Rias would interact with Goku. As a powerful devil, she would be intrigued by Goku's power and his different way of approaching battles.