Story about Undertale. SPOILERS FOR GENOCIDE AND PACIFIST AND PROBABLY EVERYTHING ELSE TOO Frisk is a nice kid, who no matter what, will not kill even the strongest monster. Chara is a devil who will kill anything she comes across. What will happen if they switch worlds? Finally complete!

It's been four years since peace and prosperity had been restored to the undergrounds where the monsters were once forced to be trapped inside. Long ago, two races ruled over Earth: Humans and Monsters. One day, war broke out between these two races. In the end of a long battle, the humans emerged triumphant. The monsters were sealed away with a magical seal. All is well until a young girl about our hero, Frisk's age, who has fallen into the undergrounds. Little do the gang find out that danger lurks around every corner in the undergrounds...

There are some things you just can't take back. No matter how many times you reset. After breaking free of Chara's grip, Frisk decides to do one final reset before defeating Sans or proceeding to the throne room. But some memories last longer than others, and broken trust isn't easy to repair. Female, aged-up Frisk. Starts out canon and then diverges. Eventual Sans x Frisk. Undertale was created by Toby Fox. I do not own Undertale, nor any of the characters. Some violent action scenes. Cover art is by amazing artists at http://www.zerochan.net/Undertale,Fanart and http://www.zerochan.net/Chara+(Undertale),Fanart

After Frisk goes missing, Caitlin, Frisk's twin sister goes looking for her in the the last place she saw her. MT Ebott, the mountain of dark legends, she finds a necklace that belonged to Frisk on the ground. Just like Frisk, Caitlin tripped and fell into the Underground. Caitlin finds things she never knew existed.