"Error! Get back here, dammit..!" Nightmare yelled into the empty basement a couple seconds after he was thrown into his cell, but the only answer he received was the cold silence. He laid his back against the back wall of the cell he was now trapped in, slowly sliding down until he had hit the floor with a small 'thud.'

"Hello.. is someone there..?"

Nightmare jerked his head towards the direction of the raspy voice. He slowly stood up, looking through the small window made of cold iron bars to the skeleton. "There is someone here..!" The skeleton on the other side stood up so they could both get a better look at each other. 

Nightmare was in his normal, goopy form, with the classic Sans look under the goop, the cloths barely visible. The strange skeleton could tell it was Nightmare instantly. Nightmare, on the other hand, had some trouble telling who the other skeleton was. The skeleton was wearing the classic sans look, but only a few things were off. First of all, the fluff. His fluff was dragging on the floor, and he had a lot covering his neck almost completely. Connecting the fluff was a diamond button, almost like the star circle button that held Dreams cape together. In addition to that, the cloths he was wearing was a long blue robe-ish jacket. 

(For whoever is going to complete the book, I was planning on it being abysstale sans, but u can change it if u wants. Gl! <3)