This is an NPC, or a non-player character.
A Burglar was a prop used in the GrowTech Pharma storyline, to represent the intruder who broke into the pharmacy. When the burglar was punched, it would say "Ow, Stop!", which is now played when punching the Awkward Friendly Unicorn (it was spoken by Mike Hommel (@Hamumu). The dummy was seen at the end of the course in the world GROWTECHPHARMA.
As of the release of the g-Virus, the burglar's data has been completely replaced by the Tombstone.
Gallery
The burglar.[1]