The War of the Janitors — Melissa Yi

At West Vincent High School, the power couple ain't the prom king and queen.
The head janitor, Gordon Pinchuk, rules the roost, harassing everyone from the principal down to the students.
Gordon saves some special grief for Birdie, the one female janitor.
Good thing Birdie's got more than a cleaning rag stuffed up her sleeve, ‘cause this war between the janitors won't end 'til one of them's laid out.
A story originally published in Sleuth Magazine, written by Derringer finalist Melissa Yi.