Just a random one shot. A man from Zoro's pirate hunting past is out to get revenge.
"You killed my brother!" The man screams wildly to make himself heard against the raging storm. He is swinging his knife to make sure the Demon understands his intent clearly, which, to his satisfaction, the Demon does. The Demon has two swords in the hideous hands that took the life of his precious brother but the Demon does not dare lift them. The Demon cannot, not without risking the life of the red vested boy.
With a feral hiss like that from a wounded animal, the Demon slowly takes a step forward. There is a maniacal glint in the Demon's eyes that make them shine almost blood-red, and upon seeing this, the man's theory is confirmed.
Roronroa Zoro is the embodiment of Hell, Satan himself, the Demon who destroyed his brother in cold blood.
"You killed my brother," The man repeats almost calmly now. He flicks off the straw hat and grabs the black hair of the unconscious boy he is sitting on, pulling the boy's head back and placing his knife against the boy's bare neck in one smooth movement. The man has been dreaming for this for every single night, for years now. He knows exactly where it will be fatal. He looks at the Demon in the eye as he laughs. "Now it's my turn."