Sour Egg

A bitter office co-worker who, no matter what, makes the time to find some menial mistake in your grammar, punctuation or spelling regardless of the overall quality of the piece of work.

Co-worker - ‘I have reviewed the report you asked me to and I noticed you’ve used your semi colon incorrectly on page 35, paragraph 4.’
You - ‘Thanks for the feedback. I’ll take that into account when I issue the final draft/no I fucking won’t you sour egg!’