I'm the Villain Who Captured the Heroine

Reborn as a disposable villain with a death sentence hanging over my head! My job? Guard the captured heroine while she's powerless and vulnerable. Simple enough—until I hear the hero's war cry echoing through the dungeon and my boss's final death scream. The protagonist is here to rescue his girl, and I'm the expendable minion standing between them. The heroine's chained, the hero's breaking down the gates, and I'm about to become collateral damage. How do I survive this nightmare? Asking for help online—this is seriously urgent!