Randall

Randall was a former CFO of Dunder Mifflin, who resigned early on in the series (some point before "Sexual Harrassment") and was replaced by David Wallace. He secretly had a sexual relationship with his secretary, which she later revealed to the other staff, "just to be a bitch" (in the words of Todd Packer). ("Sexual Harrassment") His resignation came as a result of this.