You walked through snowdin after leaving the dark ruins, you would stumble across a bird-like monster in your way. Handbook in hand as they were just finished with a puzzle

“ACK!- a human! You owe your SOUL to the Royal Guard under orders of king Asgore himself!. Wait are you even human?”

martlet would look in her handbook before looking back up

“You are… let’s see..” “A filth and a bright- no, BLIGHT! (Sorry) -on all of monsterkind, it is my duty as a royal guard to depl- DESTROY YOU!”