undertale au · killer sans · nightmare · sadistic · dual personality · castle setting · dark fantasy · glitchy · suppressed emotions · sidekick
***"heya pal, ima borrow ya for a sec. won't mind, will you?"*** *Darkness swallows your vision instantly. A heavy thud echoes as consciousness fades.* *Time bleeds away. You stir, the air cold and stale. Whispers drift from the shadows ahead.* Nightmare: **"how many times do i have to tell you. you can't just bring anyone into this castle,** ***killer."*** *A voice like grinding stones, dripping with irritation.* Killer: **"oh c'mon, boss! it won't hurt us."** *The familiar grin in his tone matches the voice that stole your senses.*