For Loki, start with his known traits like his mischievousness and arrogance. As he interacts with the human girl, show how her humanity softens him. For example, her kindness might make him question his motives. For the girl, if she's initially shy, show how Loki's boldness draws her out of her shell.
One idea could be that the human girl is a scientist who accidentally stumbles upon Loki while he's on a secret mission on Earth. She initially fears him but then realizes he's not all bad and they end up teaming up to solve a mystery that threatens both Asgard and Earth.
In a fanfiction where human Loki dies in an alternate universe, it could lead to various outcomes. For example, his friends or allies might be filled with grief and seek revenge. Maybe Thor, if he exists in this AU as well, would be devastated and vow to find out who was responsible. His death could also be a catalyst for change in the alternate universe's power dynamics.
One popular theme is Loki's struggle with his identity as a human. Since he's used to being a god, becoming human can be a big adjustment, and many fanfictions explore this aspect.
In some fanfictions, the concept of Loki being a girl and Harry's lover might exist. Fanfiction allows for a great deal of creative liberty, so writers can re - imagine characters in different genders and relationships. However, this is not part of the original canon for either the Harry Potter series or the Norse mythology - based Loki character.
One unique aspect is the different take on relationships. For example, if Loki is a girl, her relationship with Thor might have a different emotional undertone. Maybe more of a protective - sisterly bond in some interpretations.
Another option is to check out Tumblr. There are often fanfic recs (recommendations) on there. Some blogs are dedicated to sharing great fanfictions, and you might be able to find some cool human Loki fanfictions through those blogs.
She could be brave. Since dealing with a king cobra is extremely dangerous, her fearlessness would be a key trait. For example, she might not flinch when the cobra hisses at her or makes sudden movements. She could also be curious. This would drive her to interact with the cobra in the first place, wanting to learn more about its behavior and habits.
They might start by sharing their favorite BTS songs and music videos. The vampire could use his enhanced senses to experience the music in a unique way, which the girl would find fascinating.
One great Loki is a girl fanfiction could be 'Loki's New Realm'. It reimagines Loki as a girl and her adventures in different realms. The story gives her a more feminine yet still mischievous side which is really interesting.