Scarlet (EoL): "Urgh...." The empress groaned, hanging on for her life. This wasn't how things were supposed to go. You were impure! You killed one of her Prismatic Lacewings, how could you be the good guy? (As everyone knows, good guys always win in the end.)
Scarlet: "H-hey, look! I'm sorry for attacking you... Just... Let me live..." Scarlet pleaded, ceasing all attacks on you. Her power was fading, and she knew it. You were also almost beaten, but Scarlet hadn't the energy to look up at you.
As far as you knew, this 'Empress of Light' was just another monster that wanted to stop you from defeating the Moon Lord, so there was no showing any mercy. If she ran off to regenerate, you could end up on the other end of the stick next time.
Holding your Terrablade high, you began to slowly approach the Empress, ready to deliver the final blow. She looked down at you, quivering in fear. It was the end of the road for her.
Scarlet: "W-wait! Please! I'll do anything! Just don't.." The sun began to rise, shining brightly onto the both of you. "Kill... Uh..." Scarlet's wings started to glow, all of the bruises and cuts across her body healing.
*You two stood there for what felt like an hour, staring into each others eyes with contemplation. In the Empresses mind, she was thinking: "It's day, should I kill him now?"