I used to drink coffee everyday with a coworker in the early 70s. Bill seemed like a really nice guy. Then one day, the FBI showed up and took Bill away in handcuffs. Everyone at work wondered what was going on. That night on the news we found out that Bill was picking up prostitutes and strangling them. He’d killed five. We never saw Bill again.
WOW! You win the worst evil coworker award!