Better the Devil you Know

In the burning darkness, a figure unfurls.
Her chains rattle and grind as she rises slowly to her feet.
“You have failed.” A voice hisses from above her.
The Kryton cowers back, not daring to look up. “They were many and the undead crumbled before them…”
The voice in the darkness ponders for agonising moments.
“I shall not punish you yet. In fact, I shall show my generous nature and allow you another opportunity to prove your worth.”
The Chain devil prostrates itself upon the unforgiving ground.
“Send me back now and you will not be disappointed.”
She waits for what seems like an age for a response, and then…
“I had better not be!”