noun
persecutor
PER-si-kyoo-ter/ˈpɜːrsɪkjuːtər/
Someone who harasses, oppresses, or punishes others unfairly.
The persecutor pours a drink into the older man's lunch while gripping his shoulder.

Etymology
“Through” and “follow” combine in a verb meaning to pursue or hunt down. A persecutor is a pursuer in the hostile sense: someone who subjects others to cruel harassment or oppression.
In context
Now I want that signet ring upon your finger, if you please. " The old gentleman handed it over to his persecutor with a heavy sigh. He had realized that it was useless to refuse.
More examples
- She refuses to let her persecutors silence her.
- The refugees seek safety far from their persecutors.
- He confronts his former persecutor in court.
Forms
persecutor · persecutors
persecute verb — To repeatedly harass or punish someone unfairly.
persecution noun — Repeated harassment, oppression, or unfair punishment.