An irritated discolouration of the skin around the finger joints usually brought about by prolonged exposure to japanese anthropomorphic personifications of obscure antipodean mammals.
1: Dude what the hell is that on your knuckles?
2: Oh man it's just something I picked up the other day. Doctor says it's called Echidna Rash.
1: Gross!
2: Nah. It's not as bad as the other week when I had the Botniks.
1: Don't wanna know...