Creating/calling instance methods defined on class instances that are defined on that classes instance meta-class instance *head-explode*

Methods on Class Instances

ruby-1.9.2-p0 > string = "ABC"
 => "ABC" 
ruby-1.9.2-p0 > def string.thing
ruby-1.9.2-p0 >  puts 'abc'
ruby-1.9.2-p0 >  end
 => nil 
ruby-1.9.2-p0 > string.thing
abc
 => nil 
ruby-1.9.2-p0 > "abc".thing
NoMethodError: undefined method `thing' for "abc":String