Caspertruth666 is a personalitist activist and linguistic prescriptivist who created the subreddit inceltears. His main forms of activism are his attempts to alter the definition of the term incel from its original definition adopted by the lexicographer Ton den Boon. He seems to have partially named himself after the hypergamy concept, the "666 dating rule".
His/her account got suspended from Reddit permanently after doxxing someone. Some of his critics have asked him why he thinks that cherrypicked quotes represent the whole. He has never answered any of his critics.