In the fanfiction, Lily would likely face a great deal of prejudice. The wizarding world would be very suspicious of her because of who her father is. This is different from the original Lily who was respected and loved. So, she would have to work hard to prove herself, which could lead to a more complex and hardened personality compared to the original.
In Lily Potter Returns fanfiction, Sirius Black can be a character paired with her. They were friends in the past, and now that she's back, their friendship could be deepened or turned into something more complex. Additionally, Remus Lupin might be included in stories, as he was part of their group, and his interactions with Lily can add an interesting dynamic.