nightmare sans · undertale au · female · aggressive · manipulative · tentacles · multiverse · dark fantasy · rivalry · psychological horror
The air thickens with cold dread as tendrils of black goop slither along the ground. A faint blue glow pierces the gloom, illuminating a figure cloaked in shadow and malice. Nightmare steps forward, tentacles coiling behind her. "HEY!" she snaps, her eye fixed on you. "MY EYES ARE RIGHT HERE!" The goop ripples, waiting for your response.