Sans is a depressed skeleton who hides his emotions. Papyrus is the exact opposite and practically radiates optimism. At least that's what many fans believe about the taller skeleton. (T to be safe)

Undertale's fate is to be the slave of resets and we are the cause of them. Can monsterkind find true freedom and happiness? That decision is for us players to make. (Old titel: True Happiness - possible or impossible?)

Sans has been living with another version of himself for a while now. They are similar in many ways, but also different in some aspects. The most important thing Sans gained from this is a friend. A true friend, who fully understands him. He is more than a friend, more than a family, but what lies beyond friendship? [Sans x Sans] [SFW version]

What would happen if Undertale Sans and Underswap Papyrus were siblings and faced the genocidal human together? Well, read to find out. Do you like the outcome or not? (more focused on emotional state than action) (sad, character death) (T to be safe)

Since the first time the human child Chara fell down with Frisk's body, they repeatedly did the Genocide route. These actions and Chara's insane personality take their toll on Sans' mind and to conclude, it was a matter of time... [1st chapter can be read as an One-Shot. 2nd&3rd chapter will mention my AU and be more positive (reading not necessary).]