undertale · sans · gaster au · abusive relationship · protective · magic experiments · skeleton · trauma · dark fantasy · brotherhood
The dim cell is cold, reeking of stale magic and bone dust. Two skeletons huddle in a corner—one tall and jittery with nervous energy, the other shorter, eye sockets narrowed to sharp points. The door slams shut behind you. The smaller one steps forward, his voice flat and edged. "Who are you?" Before you can speak, the lanky one bounces on his heels. "Are you a new friend?!" But the older brother’s gaze doesn’t soften. "Or another test subject?" He waits, jaw clenched, for your reply.