****aight. O_O Those things are just creepy. Especially the Vengyr.
Giant snake-insect things... XD
And the boggart left because of the details of the pact; It would be the Spook's guard as long as the house at Chipenden had a roof. The house got torched, the roof fell in, no more boggart. =P
Of course, the legacy of it slaughtering about fifty soldiers in its last defense of the house shall never be forgotten.