My first is in bridge, but not in ridge.
My second is in awake and in mistake.
My third is in danger, but not in ranger.
My fourth is in flange and in orange.
My fifth is in spline and in nine.
My last is in river and in diver.
My whole likes the darkness.
What am I?
[Ref: ZOMD] © Mr Stone
Hint: The first letter can only be B.