Broadly speaking, peer seems to have two meanings, looking intently and being partially visible.
a). She peered into the darkness.
b). The moon peered from behind dark clouds.
However, I have difficulty understanding ‘peer’ with ‘around something’ as follows. Would you help me? (‘Around’ often annoys me!)
Go, Harry pleaded with him silently, go with Snape … go … Mrs. Norris was peering around Filch’s legs…. Harry had the distinct impression that she could smell him. (Harry Potter 4 [US Version]: p.470)[Bold font is mine]
N.B.: Mrs. Norris is a cat. Harry is in an Invisibility Cloak.
All of them were looking at something Harry couldn’t see and sniggering heartily. Pansy’s pug-like face peered excitedly around Goyle’s broad back as Harry, Ron, and Hermione approached.(Harry Potter 4 [US Version]: p.511)[Bold font is mine]
PS: *No.1:* I thought at first the cat is just walking between somebody’s legs like forming a figure 8, but I couldn’t find a good example on the Net or YouTube. Or is the cat looking at a specific thing, for example, Harry as a smelling point or Filch’s legs? Or, is it similar to ‘looking around something’: to visit somewhere, walking around it to see what is there? (Unlikely… well, the sentence pattern seems similar, though…)
No.2: I wish I could find any dictionary says ‘around’ means ‘from behind’.