Someone who comes from Devonport or the area round it, and reckons they're the hardest person to walk this earth, but no one will disagree with them because even if the swill aint the hardest guy around him and his mates will outnumber anyone who disagrees with him about 15 to 1 and kick their head in, leving them for dead after kicking the unconcious body around the road.
*Random person walks past, trying not to be noticed*
Swill1: Oi! you startin?
Person: uh, no
*Swill1's mates gather round and Person gets beaten up and left in the gutter*