someone or something that you really hate or that really annoys you People who use jargon are his particular bête noire.
bête noire
A person or thing that is particularly disliked. For example, Calculus was the bête noire of my freshman courses. This phrase, French for "black beast," entered the English language in the early 1800s. For synonyms, see pain in the neck; thorn in one's flesh.