Blackfrost

Blackfrost is the non-binary ship between Loki and Natasha Romanoff from the Marvel Cinematic Universe fandom.

Canon
Due to being enemies, Loki and Natasha have no scene involving them as good friends.

Marvel Cinematic Universe
After Loki returned to Earth, Natasha was picked to be one of the Avengers to fight him. Knowing that facing Loki would save Hawkeye from the control that he has over his mind, Black Widow agreed to recruit the Hulk for their plan to fight Loki. Shortly Natasha's allies found and caught Loki, she flew the jet they used to transport Loki to their base; and on the way there Loki's brother joins them.

With Loki in their custody, while his mind controlled pawns are continuing the work he has got them to do on his behalf, Natasha goes to see Loki in his sell. In hopes that she can find out what he is planning. Like Loki Natasha tricks the information out of him, while making him believe that his threats had gotten to her, and once Loki realized that she had played the same trick that he commonly uses on him he was surprised by it. Even though Natasha was able to learn that Loki plans to awaken the Hulk, Black Widow and her allies weren't able to prevent Loki's escape when his pawns attacked the ship. Despite being defeated when Loki got away, Natasha was determined to do what ever she can to stop his plans for Earth, that came in the form an alien invasion.

With help from her allies, Black Widow and the rest of the Avengers were able to save Earth and bring Loki back into their custody. Since their shared goal to stop Loki is what helped Natasha to help with her allies. Natasha later sees Loki off as Thor brings his brother back to his home realm, so Loki could face his punishment. While she takes a short brake from what Loki has put her through.

Moments

 * Natasha uses Loki's staff to close the portal.
 * Natasha takes part in the mission that reclaims Loki's staff back from HYDRA.

Fanon
The shipping began in one scene of The Avengers when Natasha asked Loki if he's mad when he was arrested. Fans believed if Natasha and Loki are canon, Loki would say to Natasha something that would make up for the Avengers then hook up with her.

Loki and Natasha's personalities clashed but fans think it mix well. Other than that, they believed that the ship work as both are reformed villains. Fans feel like if they were to get along, Natasha would accept Loki for who he is, having to hear about his hard background. She would be more understanding to him and be someone who would always have his back. It would start off as a friendship and grow into something even bigger with time.

Many fanworks involve Loki being punished after the events of The Avengers by being changed into a human, sometimes Natasha was his handler or teacher, or sometimes they just meet again. Other than that, some also involving Natasha being included in canon events where she was not present, like Thor: The Dark World or Thor: Ragnarok.

Fandom
FAN FICTION

DEVIANTART