That makes 19! If anyone has friends they really wanted to join, I can allow a couple more, but the game will be full pretty soon. Definitely starting tomorrow at noon.
Unfortunately, roles will have to be random. It's more of a game balance thing than anything else. You wouldn't want to be targeted just because you prefer to be the bodyguard, after all, not would you want a friend targeted immediately after being revealed as a werewolf because it's likely you wanted to be on the same team.
I actually had to kick a player out if Spyfall (not the game on E) because his preferences were breaking the meta of the game.