You can start by looking on Archive of Our Own (AO3). It has a vast collection of fanfictions, and there are likely many dedicated to Jughead and Toni. Just use the search function and type in their names.
One great Jughead and Toni fanfiction is 'The Riverdale Connection'. It beautifully portrays their relationship in a way that feels very true to their characters. It dives into their shared experiences in Riverdale and how they support each other through various challenges.
Yes, there are likely fanfictions with such a plot. Fanfiction writers often explore different scenarios and relationships in the Riverdale universe, and a situation where Jughead takes a bullet for Toni could be a very dramatic and emotional storyline that many would be interested in writing about.
I'm not sure specifically, but it's possible that fans have written stories where they are in a relationship and sleep in the same room without any adult - themed scenarios. Maybe it's part of a story where they are on a camping trip with friends and end up sharing a tent for safety reasons and that's all there is to it.
The main theme would likely be self - lessness. Jughead's act of taking a bullet for Toni is an extremely selfless one. It could also explore the theme of mortality, as the bullet could potentially end Jughead's life. This would make Toni and other characters face the reality of death. Additionally, it might touch on the theme of trust. Toni would have to trust that Jughead's sacrifice was not in vain and that she can carry on in a way that honors his act.
Fanfiction.net might also be a place to look. However, you need to be careful and read the descriptions carefully. Some authors will clearly state if their story is appropriate for all ages. You can also filter by genre or rating on the site to narrow down your search for a non - adult 'jughead sleeps with toni' fanfiction.
It might lead to a redemption arc for Jughead. He could realize his mistake and try to win Betty back. He might start doing all kinds of nice things for her in the fanfiction, like writing her letters or bringing her favorite things. Betty, on the other hand, could be hesitant to forgive him at first.
She might be really angry. In the context of fanfiction, Betty could see this as a betrayal of their relationship in the story's universe. She might confront Jughead immediately and demand an explanation.
There's also a chance he would be worried and a bit scared. They are both young, and he may be concerned about whether they are ready for this big step. He might worry about how they will afford to take care of a baby and still pursue their own dreams.