A song and a dance (WStale)

Okay, this is an au I made. WS stands for Whistle Song. The story of this tale is: 'Toriel grew up a merchant's daughter, rich and successful. After an incident where the murder of six humans took place, she was locked in her home for safety. Outside, Papyrus grew stressed and sad, for his brother Sans was a mute. He COULDN'T speak, even if he wanted to. After listening to birds day after day, Sans eventually started whistling. It wasn't irritating, it was pleasant to hear his bird song. When a human named Cerys falls into the underground, people discover she is like a swan. always able to dance. When she meets Sans, the mix between their talents is beautiful: A song and a dance.'