Used in Ylvis brother's video "The Cabin". Derives from the norwegian saying "det finnes ikke dårlig vær, bare dårlig _klær_". This saying has a rhyme to it, so when they sang it in english they made up the word kleather to make it rhyme.
there is no such thing as bad weather, only bad kleather
Klerton is usually a person who dresses like he's in his 40's, plays the piano, refuses to cut his long hair, likes parrots and is a great friend who makes you laugh.(Keep him tight, he gives good hugs)