herself vs whatshisface

herself

pron
  • Her; the female object of a verb or preposition that also appears as the subject. 

  • She; an intensive repetition of the female subject, often used to indicate the exclusiveness of that person as the only satisfier of the predicate. 

  • The subject or non-reflexive object of a predicate; she (used of upper-class ladies, or sarcastically, of women who imagine themselves to be more important than others) 

whatshisface

noun
  • A person whose name is either unknown or forgotten 

How often have the words herself and whatshisface occurred in a corpus of books? (source: Google Ngram Viewer )