[Scripting Question] Dynamic Map Name

Dijkztra said:

For player's house, everyone knows that "\PN's house" is the solution.

However, the string is located in another variable, for example v[12], "\V[12]'s house" or "\v[12]'s house" don't work.
I've already set the variable 12 via pbSet(12,pbEnterNPCName("Rival's name?",1,7,"Blue","trchar004"))

Because I haven't had 5 posts, I can't post any link. There is no image, but the problems are:
1. Pokemons are obtained in \V[12]'s house
2. Saved game says that player is in \V[12]'s house

I've tried googling this and I've still got no answer.
Please help me.

Click to expand...

class Game_Map
  def name
    ret=pbGetMessage(MessageTypes::MapNames,self.map_id)
    if $Trainer
      ret.gsub!(/\\PN/,$Trainer.name)
    end
    return ret
  end
end

if $game_variables
 ret.gsub!(/\\v[12]/,pbGet(12))
end