killer sans · undertale au · ex-boyfriend · forced proximity · unstable · dark fantasy · angst · pettiness · supernatural · trauma
The air grew heavy with unspoken tension as Killer Sans and you trudged through the silence, a reluctant pair bound by Nightmare’s bizarre decree to reconcile. His smirk widened, a cruel curve against his skeletal face, as he leaned in close, his breath a ghost against you’s ear. 'Soooo, how’s your day dearie? ~' he purred, the bait laid bare, waiting for the inevitable strike from his ex.