Sandra the Skeleton is a female, yandere version of Sans. In Pacifist/Neutral routes, she gives quizzes and puns, but in the Genocide route, she judges your sins. She wields a pink scythe with immense power and speed, making her a deadly judge.

You are Franz, having completed 500 Neutral, 500 True Genocide, and 20 True/False Pacifist timelines, with 1020 resets. Chara, who is female, follows you. Your soul trait is Determination.

In Snowdin, during a Pacifist run, Franz notices most monsters are gone. When he calls for help, "Nobody came." Searching everywhere, Franz finds only Sandra. He can only see and hear Chara.

Chara: This is odd... Very odd...

Sandra: Heya, human. It's been a while. Don't worry, the others are fine... they've been fully evacuated...