Yes, there might be some out there. You can start by checking popular fanfiction websites like Archive of Our Own. Just search for 'riff loves bernardo' and you'll likely find a selection of stories.
You could also try FanFiction.net. Although it's a bit more general, there might be some 'riff loves bernardo' fanfiction there. Another option is to check Tumblr. Sometimes, fans post snippets or links to their fanfiction on their blogs.
One possible plotline could be that Bernardo gets into a dangerous situation, like being trapped in a burning building, and Tony risks his life to save him. Maybe there's a feud between their groups, but Tony's sense of justice or his personal feelings for Bernardo override that.
I'm not sure which specific 'tony saves bernardo fanfiction' is available. You could try searching on popular fanfiction websites like Archive of Our Own. They usually have a wide range of fan - created stories.
The 'riff raff top stories' could cover a wide range of things. It might include stories of people who have overcome great odds in a rather unorthodox way. For example, stories of street performers who became famous overnight, or small - scale entrepreneurs who started from very humble beginnings and made it big. It could also be about unique cultural events or happenings in a less - known part of the world that are now getting some attention.
Well, it could lead to a major shift in the story's direction. Maybe Tony's friends would react differently and it could change the whole plot dynamic.
The forbidden riff might have a backstory tied to a specific band's internal drama, or it could have been banned for causing chaos or disruption at live performances. Maybe it even has a supernatural or mythical tale attached to it.