The title explains it all...

It was supposed to be a search and rescue with your two closest friends. With your 'brother' Frisk missing now two days and that foster home giving less than a damn, it was up to you and your best friends to follow his one clue. But what happens when one little clue leads to a situation larger than life? Will you survive or will you fall in the cruel world of Underfell?

(Y/n) goes to Mt. Ebbot in search of her brother Frisk. But what she finds instead amazes her.