Forgiveness

Frisk went through the ruins and met a skeleton by the name of Sans. The two became friends, lovers, and fell for each other, as they planned their life on the surface. However, when Frisk comes home one day to find Sans and Muffet in a sensual embrace, her heart is broken. Running out, she gets caught up in a snow storm and eventually resets. After the reset, Chara lures Frisk into letting them take control. Agreeing, the already broken-hearted Frisk is forced to watch everyone she met and loves being slowly murdered, feeling their dust on her hands. After winning control in her battle with Sans, she resets the world again, planning your delete herself to prevent horrible things from ever happening again. However, the thought of leaving everyone behind crushes her, as she starts a new game, determined to stay as far from Sans as she can get. Her plan is to save the monsters and kill herself in the process, so she won't ever have to bear the pain of what she's already experienced again