Pypar, also known as Pyp or Monkey, is a ranger of the Night's Watch.
Pypar travelled in a mummer's troupe before joining the Watch. He can imitate hundreds of accents and loves to act. He claims to be able to tell where somebody is from just by how they speak.
A Game of Thrones
After the arrival of Samwell Tarly at Castle Black, Pyp at first tries to prevent Jon from interfering in his training bout with Halder. After Jon ignores him and Ser Alliser Thorne sends Albett and Rast after him, Pypar joins Jon's side, and helps him take down Rast. He is later present when Jon threatens Rast in his cell, warning him off hurting Sam.
A Feast for Crows
Pyp and Grenn lament to Sam and Edd about how distant Jon has been since being elected as Lord Commander. He feels like Jon has abandoned the friends that helped him to get to the position he holds.