Underswapalphys Stories

[Underswap Papyrus x reader] You have a secret. You are the last of your kind, shapeshifter / Human hybrid. The very culmination of your being constantly pleads for you...

After months of not being around anybody much since Undyne was recovering from almost dying. She's been so afraid that she would hurt everyone she loves and cares about...

As usual, Sans comes back from training, happy and excited, except this time, he arrives home 'marked'. Papyrus is not pleased, until he finds the creative little secret...