Retro 80-90s anime only remembered through screenshots
I've only ever seen the scene in the form of screenshots. It look liked late 80's, early 90's animation, probably fantasy or maybe fantasy sci-fi.
The henchman, who I presume was defeated by the main characters, was a a fairly humanoid dude while the main villains kinda looked like large humanoid skeleton bug monster things (maybe didn't move any kinda mouth when they talked) in perhaps robes, all standing (sitting?) over him on this big circular throne area that was pretty dark.
The henchman requested he be honor killed for his failure but the baddies said something along the lines of "No. Despite your failure today, you have been of great help to the empire. Go now and rest to make use of your skills another day". The henchman seemed shocked at this.