It is tricky territory, but I believe that Courier Six would fall into appable territory. When we say "fandom OCs" we mean characters who aren't int he game at all and are wholly original.

That said, the more detail you can give us the better. You don't have to do a step-by-step guide (being as the game is a HUGE sandbox that would be practically novel length!) but notating which choices that they made and what sidequests of note that they did in the history, and talking about how those sidequests and choices affected them in the personality would eb great. Applications in this game are more or less just for player and mod reference!