Speculations on the Boggart

[girl_next_door704]

No: HPFGUIDX 113063

Hi,
  I've been thinking about the Boggart ever since I read the concept 
in PoA; so this question came up in my mind when I was reading 
OotP for the second time.

  In the third book, Professor Lupin tells the students in their 
first class that nobody knows what a Boggart looks like in the dark. 
In OotP, in Number 12, Grimmauld's Place, when Mrs.Weasley asks Mad-
Eye Moody to confirm whether the drawer in the upper floor has a 
Boggart in it and he looks through the ceiling, what exactly does he 
see? Does he see the real form of a Boggart? If he does, then why 
doesn't he make it known to others? If he sees what he fears most, 
how does the Boggart then supposed to know he's watching? Does it 
feel his glare?

                                                           Neha S.