penitent vs unregretful

penitent

noun
  • One under church censure, but admitted to penance; one undergoing penance. 

  • One under the direction of a confessor. 

  • One who repents of sin; one sorrowful on account of their transgressions. 

adj
  • Feeling pain or sorrow on account of one's sins or offenses; feeling sincere guilt. 

  • Doing penance. 

unregretful

adj
  • Not regretful; having no regrets. 

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