crazy person, usually male, as a rule cannot type ot text without making large, frequent mistakes, which subsequently become the object of ridicule in his social circle. The term was coined because of a mistake involving nober being written as noper.
"you fucking noper" to show contempt at a foolish behaviour or just to remind the noper that he is a noper
Adjective defining a person who does not demonstrate an obvious personality. Or a very boring individual.
A butter face is someone who has a nice body but her face is unattractive a noper is someone who can be good looking but is dull and lame to be around or in other words lacks a personalty.