One possible plot could be that Lauren is in a state of shock after being hit by the truck. Her friends in the 'Lost Girl' world then rush to her aid. They might use their supernatural powers to try and heal her or at least keep her alive until proper medical help arrives. There could be a lot of emotional turmoil as they fear losing her.
Kenzi would be an important character too. She's Lauren's friend and has a big heart. She'd probably be the one running around trying to get all the necessary supplies or information. She could also be the comic relief in the otherwise tense situation, but still be deeply concerned about Lauren's well - being.
A fanfiction might explore a day in the life of Bo, An, and Lauren as friends. They could go shopping together in the Fae world. Bo is excited about trying on different outfits, An is a bit more reserved but still enjoys the experience, and Lauren is fascinated by the unique Fae fashion. They then go for lunch and talk about their hopes and dreams. This simple day out strengthens their friendship as they get to know each other on a more personal level.
It could be Bo. Since they have a complex relationship in 'lost girl', Bo might feel the need to discipline Lauren in the fanfiction for some reason, like if Lauren's actions put Bo or their friends in danger.
A fanfiction could be set in a parallel world where Bo, An, and Lauren have different roles but still maintain their friendship. For example, Bo could be a powerful Fae leader, An could be her advisor, and Lauren could be a healer in her court. They face political intrigue and threats to Bo's leadership. Working together to protect Bo and her reign, they solidify their friendship in this new and challenging setting.
One common theme is the struggle between their different worlds. Bo is a succubus and Lauren is a human doctor, so there's often the theme of how they bridge that gap. Another theme is love against all odds. They face many challenges in the show, and fanfiction often explores how their love endures. Also, loyalty is a big theme, as they have to be loyal to each other and also to their own principles.
Fanfiction.net is also a good place. There are many fans who post their Lost Girl Bo and Lauren fanfictions there. However, the interface might be a bit more dated compared to AO3, but still has a lot to offer.
One great fanfiction could be 'The Unseen Bond'. It delves into the deeper emotional connection between Bo and Lauren that might not have been fully explored in the show. It has some really interesting character development.
Without more information, it's impossible to say who Lauren is. She could be an ordinary girl, a character in a made - up story, or someone known within a particular group.
A plot could revolve around Lauren getting into some trouble with a powerful Fae group, and Bo has to use all her powers and influence to rescue her. This would show Bo's loyalty to Lauren and how far she's willing to go for her. Also, during the rescue, they could have some deep emotional conversations that further develop their relationship.