At first, it would be rocky. Loki is used to being a trickster and Tony is a bit of a control freak. But over time, they'd start to respect each other. Loki would see Tony's intelligence and resourcefulness, and Tony would see Loki's power and potential for good. Eventually, they'd become like family, looking out for each other.
In the beginning, Loki would be distrustful of Tony and his motives for adopting him. Tony would be cautious as well, not fully trusting Loki not to pull some sort of trick. As they spend more time together, Loki might start to open up about his past traumas in Asgard, which would make Tony more sympathetic. Tony would introduce Loki to his world of technology and science, which Loki would find both fascinating and useful. Their relationship would grow into a deep friendship, with Loki using his magic to assist Tony in his superhero duties and Tony providing Loki with a stable home and a sense of belonging.
Loki's mischievous nature would make their relationship full of surprises. He might play pranks on Tony, which could initially annoy Tony but later become a source of amusement. His cunning could also be an asset, as he could outwit Tony's enemies. However, his tendency to be self - centered might cause some friction, as Tony is used to teamwork. But overall, it would create a dynamic and interesting relationship.
Their relationship would be a slow - burn. Loki might play some pranks on Tony at the beginning, which would annoy him. However, when they get into a really tough situation, like being trapped in a dangerous dimension, they have to rely on each other. Loki could use his magic to keep them alive, while Tony uses his engineering skills to find a way out. This shared experience would bring them closer and make them realize that they can be good partners.
Initially, Tony's relationship with deaged Loki is one of pure obligation. He has to keep Loki safe and figure out how to get him back to normal. However, as he takes care of Loki, he discovers that Loki has a curious and intelligent side even in his deaged form. Loki, for his part, is used to being alone but starts to enjoy Tony's company. They might have some arguments along the way as Loki still has his stubborn streak. But through shared experiences, like facing a common enemy together or just spending time exploring Earth, their relationship evolves into a deep and trusting one.
One possible plot could be Loki, having lost his place in Asgard perhaps after some misdeeds, is found by Tony. Tony, being the genius with a big heart (underneath his playboy exterior), decides to take Loki in. Loki initially resists but gradually warms up to Tony's world of technology and Earthly comforts. They might team up to fight a common enemy, with Loki using his magic and Tony his high - tech gadgets.
Their relationship could develop in a rather chaotic way. Loki might play pranks on Tony using his magic, which would annoy Tony at first. However, as Tony gets used to Loki's antics, he starts to see the humor in it. Meanwhile, Loki starts to admire Tony's determination and ability to create amazing things. They could have a love - hate relationship for a while, until a big event, like an alien invasion, forces them to fully trust and support each other.
He might just be a big fan of Loki himself in the fanfiction world. So, he wants to protect the stories that feature Loki.
In the fanfiction, Loki may have developed a sense of respect or even friendship for Tony. They are both very intelligent characters. Loki might admire Tony's ingenuity and courage. So when he realizes that Tony is in danger in Siberia, his new - found feelings for Tony drive him to save his life. Also, Loki might be bored with his usual villainous ways and wants to do something good for a change, and saving Tony seems like a good start.
Their relationship could develop in a mentor - mentee way at first. Tony would teach Peter about science, technology, and how to be a better superhero. As time goes by, they would become more like father and son. Peter would start to look up to Tony not just as Iron Man, but as a dad. For example, they might have movie nights together or Tony would help Peter with his school projects.
Loki might interact with her in a rather mischievous way at first. He could play little tricks on her just to see her reaction, but also be secretly impressed by her intelligence, which she got from her father. For example, he might magically move her tools while she's working on a project, and then be amused when she quickly figures out how to get them back using her own smarts.
Their interaction would be full of tension at first. Loki is a trickster and Tony is a skeptic. Loki would likely use his charm and magic to try to throw Tony off, while Tony would be using his sarcasm and intelligence to counter Loki's advances. It would be like a clash of two very different personalities, one from the world of magic and the other from the world of science and technology.