The Devil's Dictionary: Abstainer (n.)

A weak person who yields to the temptation of denying himself a pleasure. A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the affairs of others.

(Note to Gentle Readers perhaps not familiar with the details of Ambrose Bierce's fascinating life and career: his target here is the demure and lovely belles of the Temperance Movement.)