OK but why does Marius have a poster in his room that says “Javertas 830?”

Is Marius a member of the Javert fanclub??? Are there 830 members in the Javert fanclub? HAS THE JAVERT FANCLUB EXISTED SINCE 830? What is going on here???

(ACTUALLY maybe Vampirevert as an immortal has indeed existed since 830, and like any good vampire (just ask Lestat) he has his own fanclub, hmmmm…)