AU where Joly’s first name is Roger and for the first day of school every year he shows up wearing pirate shit for when a teacher inevitably calls out Joly, Roger in class 

He meets Grantaire in his freshman year of high school when the other boy aggressively insists on being called R

No one is really surprised when they’re both sent to the office for talking like pirates for the rest of the class. 
And that’s where they meet Bossuet, who had taken the fall for some Pontmercy kid

Needless to say, he is 100% down with pirate lingo, the principal has no idea what to do with them, and it’s only day one