PIP/NSI these obvious choices ASAP:
Your fellow worker who does nothing but attends meetings.
Your colleague who is addicted to International Business Travel and spent most of their time looking for and scheming for their next company paid unwarranted business trip.
Your acquaintance who have schemed to get lucrative ex-pat assignments one after another and only live for that extra cash and perks.
Coworkers who worked the LCS fraud.